PROCEEDINGS

OF THE

AMERICAN ACADEMY OF ARTS AND SCIENCES.

PROCEEDINGS

OF THE

AMERICAN ACADEMY

OF

ARTS AND SCIENCES.

NEW SERIES.
Vol. XIX.

WHOLE SERIES.
Vol. XXVII.

FROM MAY, 1891, TO MAY, 1892.

SELECTED FROM THE RECORDS.

BOSTON:

UNIVERSITY PRESS: JOHN WILSON AND SON.

1893.

z.3 i (o

NOTE.

The publications of the Academy in octavo form, called
" Proceedings," were begun in 1846, by Dr. Asa Gray, then
Corresponding Secretary. The original plan was to print
with the proceedings of the meetings of the Society abstracts
of the papers presented, reserving the more formal finished
papers for the quarto publications, called " Memoirs." This
practice was continued until 1873, by Professors W. B. Rogers
and Joseph Lovering, who succeeded Dr. Gray in the same
office, and during these twenty-seven years eight volumes
were published. Meantime, on account of the difficulty of
procuring abstracts, that feature of the plan fell into disuse ;
while the greater convenience of the octavo form for most
scientific subjects, as well as its greater economy, led to the
printing of papers in extenso amidst the proceedings of the
meetings. For this reason, the undersigned, on assuming
the direction of the Academy's publications, in 1873, published
the scientific papers separately, under appropriate captions,
and made the proceedings of the meetings an appendix to the
papers ; and daring the nineteen years he has held the office
of Corresponding Secretary an octavo volume thus made up
has been published each year.

The original idea of incorporating with the proceedings of
the meetings such brief abstracts of verbal communications as
may be furnished by the authors was an excellent one; and
although latterly the plan has been seldom followed, it has
been by no means abandoned. It should be borne in mind
by members that this method of partial publication is still
practicable, and may be very useful for preliminary notices
during an extended investigation.

JOSIAH P. COOKE,

Editor Vols. IX. to XX VII. inclusive.

CONTENTS.

Page
I. Some Considerations regarding Helmholtz's Theory of Con-
sonance. By Charles R. Cross and Harry M. Good-
win 1

II. Note on the Dependence of Viscosity on Pressure and Tempera-
ture. By Carl Barus 13

III. What Electricity is : Illustrated by some New Experiments.

By W. W. Jacques 19

IV. Further Additions to the North American Species of Laboul-

beniaceos. By Roland Thaxter 29

V. On a Theorem of Sylvester's relating to Non-degenerate

Matrices. By Henry Taber 46

VI. Researches on the Volatile Hydrocarbons. By C. M. War-
ren 56

VII. Note on a Criticism of the Author s Apparatus for Fractional

Condensation. By C. M. Warren 89

VIII. On the Formation of the Anhydrides of Benzoic and Substituted
Benzoic Acids. By George D. Moore and Daniel
F. O'Regan 93

IX. Note on the Relative Position of High Temperature Melting

and Boiling Points. By Carl Barus 100

X. On Bivalent Carbon. First Paper. By J. U. Nef . . . 102

Vlll CONTENTS.

Page
XL Note on the Representation of Orthogonal Matrices. By

Henry Taber 163

XII. Descriptions of New Plants collected in Mexico by C. G.
Pringle in 1890 and 1891, with Notes upon a few other
Species. By B. L. Robinson 165

XIII. On Certain Products of the Dry Distillation of Wood:

Methylfurfurol and Methylpyromucic Acid. By Henry

B. Hill and Walter L. Jennings 186

XIV. On Certain Derivatives of Pyromucamide. By Charles

E. Saunders 214

XV. On the Least Number of Vibrations necessary to determine
Pitch. By Charles R. Cross and Margaret E.
Maltby 222

XVI. The Tropical Faunal Element of our Southern Nymphalinm

systematically treated. By Samuel H. Scudder . . 236

XVII. Trianilidodinitrobenzol and Certain Related Compounds.

By C Loring Jackson and H. N. Herman . . 252

XVIII. Preliminary Communication on the Host oj Nectonema Agile,

Verr. By Henry B. Ward 260

XIX. On the Thermal Conductivity of Cast Iron and of Cast Nickel.

By Edwin H. Hall 262

XX. On some Experiments with the Phonograph, relating to the
Vowel Theory of Helmholtz. By Charles R. Cross
and George V. Wendell 271

XXI. The Reactions of Sodic Alcoholates with Tribromtrinitrobenzol.
Second Paper. By C. Loring Jackson and W. H.
Warren 280

XXII. On the Action of Water upon Tribromtrinitrobenzol and Tri-
bromdinitrobenzol. By C. Loring Jackson and W. H.
Warren . . . 317

CONTENTS. IX

Page

Proceedings 325

Memoirs: —

Edward Burgess 357

George Bassett Clark 360

William Prescott Dexter 363

Thomas Sterry Hunt 367

Joseph Lovering 372

George Hinckley Lyman 385

David Humphreys Storer 3S8

Cyrus Moors Warren 391

Sereno Watson 403

George W. Cullum 416

John C. Fremont 422

Thomas Hill . . . • 426

Joseph Leidy 437

Noah Porter . . 442

John Couch Adams 444

George Biddell Airy 446

Wilhelm Eduard Weber 449

List of the Fellows and Foreign Honorary Members . . 451

Statutes and Standing Votes * 459

Index 469

PROCEEDINGS

OF THE

AMERICAN ACADEMY

OF

ARTS AND SCIENCES.

VOL. XXVII.
PAPERS READ BEFORE THE ACADEMY.

I.

CONTRIBUTIONS FROM THE PHYSICAL LABORATORY OF THE
MASSACHUSETTS INSTITUTE OF TECHNOLOGY.

XXXVII. — SOME CONSIDERATIONS REGARDING
HELMHOLTZ'S THEORY OF CONSONANCE.

By Charles R. Cross and Harry M. Goodwin.

Presented June 10, 1891.

The present paper contains the results of a number of experiments
relating to certain aspects of the theory of consonance and dissonance
put forth by Helmholtz in the Tonempfindungen. In that work
the author gives as the number of beats producing the maximum of
harshness from thirty to forty per second, reaching this conclusion
from a consideration of the amount of dissonance of various different
chords in different octaves.

Ma}*er * studied the relation of the number of beats causing the
greatest harshness to the absolute pitch, and showed that there is
a marked rise in this number as the pitch becomes higher. The
beats studied by Mayer, however, as he himself pointed out, are
in several respects different from those which occur in the case of
mistimed unisons. They were caused by rotating a disk, which

* American Journal of Science, Vol. CVIII. p. 211 ; Vol. CIX. p. 267.

VOL. XXVII. (N. 8. XIX.) 1

2 PROCEEDINGS OF THE AMERICAN ACADEMY

was provided with a circle of holes near the circumference, hetween
a vibrating tuning-fork and a resonator, the number of beats per
second being of course greater as the speed of the disk was greater.
Hence the sound-wave reaching the ear was not at all a compound
wave due to the superposition on one another of two simple sound-
waves slightly differing in length, as in ordinary beats, but merely
a series of simple waves with gaps, as it were; while the passage
from maximum to minimum intensity in the sound reaching the
ear was very different in its character from that actually occurring
with ordinary beats. In referring to such beats as those studied
by Mayer, we shall for the sake of brevity designate them as " in-
terruptional beats," and the ordinary beats we shall call "inter-
ference beats."

We have thought it desirable to ascertain what results would be
reached in different registers with interference beats, such as are
present in actual dissonances. It was of course necessary to em-
ploy simple tones. Our method was a direct one, viz. to produce
two such tones simultaneously, and to vary the pitch of one of these
by known amounts, estimating by the ear when the sound became
the harshest.

As a source of sound we employed the cylindrical resonators of
Koenig, which were sounded by gently blowing across the opening
a stream of air from the brass, slit-shaped "universal embouchure "
made by the same maker. We found these tones to be very pure
and loud, while their pitch could be varied with great readiness
without altering the intensity of the sound emitted. The set of
resonators employed ranged from Solx to Mlh, the ranges of succes-
sive resonators overlapping slightly. The two embouchures were
connected to a Y by rubber tubes, and placed on adjustable sup-
ports in suitable relation to the apertures of the two resonators to
be sounded. The strength of the blast was regulated by a stopcock,
and the bore of each rubber tube could be closed more or less by a
clamp, so that the force of the jet of air at each resonator could be
adjusted with all needed delicacy. Thus the intensity of the notes
given out by the two resonators could be adjusted so that they were
exactly equal in loudness. This was done by causing the tones to
beat slowly, and so adjusting the apparatus that there was ap-
parently an absolute silence when the sound fell to its minimum
intensity. No difficulty was found from any whirring of the sheet
of air as it struck the edges of the aperture, since by proper adjust-
ment this could be made quite inappreciable. Having once made

OF ARTS AND SCIENCES. 3

the necessary adjustments, the pitch of either note could be varied
by drawing out or pushing in the lower half of the resonator. The
actual pitch of the note given by the resonator was in all cases
determined by comparison with a tuning-fork of known rate. As
the pitch of the resonator when blown is to a certain extent de-
pendent on the position of the embouchure and the strength of the
blast, it would not be safe to assume that the actual note given
by the resonator was that marked upon it. Neither resonator
when sounded sensibly affected the pitch of the note given by
the other.

The determination of the point at which the harshness of the
dissonance produced by the tones of the two resonators reaches a
maximum is of course a very difficult problem to be solved exactly.
It is, moreover, a question still to be investigated, whether pre-
cisely the same results would be reached by different observers
possessed of equally good perception. The following figures given
in Table I. were ascertained from a long series of observations by
one of the writers (Mr. Goodwin). They are liable to an error of
a single beat in either direction, possibly somewhat more in one or
two cases. They furnish, however, the first series of direct meas-
urements of this kind which we know.

1

'ABLE

I.

Ut2

Utz

Solz

Uti

Soh

Vth

Mi,

19

26

29

32

36

41

45

It will be noticed that the result for Uti7 32 beats per second,
agrees very closely with the number 33, which Helmholtz gives
for maximum dissonance in the middle registers. He found that
of the ordinary musical intervals, b' c", as he designates it, was the
most dissonant, and as this gave 33 beats per second he considered
this number as giving the harshest effect for tones of corresponding
pitch.

The notes furnished by the resonators are also well adapted for
the direct study of the limit at which the beats cease to be audible
when their number is increased. As the interval between the beat-
ing notes is increased, the beats heard become fainter and fainter
until they disappear. It is all but impossible to fix upon the pre-
cise point of disappearance, since the change in loudness of the
beats is so gradual. But, as will presently appear, our results
clearly show that the maximum number of beats perceptible, like

4

PROCEEDINGS OF THE AMERICAN ACADEMY

the number giving the maximum dissonance, varies greatly with
the pitch of the notes sounded.

The pitch of one of the resonators was varied so as to run upward
and downward through the vanishing point of the heats. This pro-
cedure was extremely tiresome, and the values obtained were found
to be considerably influenced by fatigue of the ear. The following
table (Table II.) gives the results obtained when the ear was in
good condition. The first column gives the rate of vibration of
the lower note, the next four the rate of the upper note as found
in corresponding series of observations; the seventh column gives
the number of beats, and the last the interval between the two
notes.

TABLE II.

Lower
Note.

Upper Note.

Mean.

Beats.

Interyal.

17*2 128

1.
175

2.
170

3.
177

4.
173

174

46

Fourth +.

Ut3 256

328

321

326

329

326

70

Major third +•

Sol3 384

467

458

469

460

464

80

Major third — 16 vibrations.

Uti 512

620

616

618

611

616

104

Minor third (nearly).

Soli 768

882

890

886

890

887

119

Tone + \ tone (nearly).

UtB 1024

1160

1167

1160

1163

1163

139

Tone + 11 vibrations.

Mi5 1280

1420

1424

1421

1418

1420

140

Tone — \ tone (nearly).

These figures abundantly confirm for interference beats the results
already reached by Mayer for interruptional beats, viz. that the ear
is capable of appreciating a greater number of beats as the pitch of
the beating notes rises. They also show very beautifully the in-
creasing consonance of small intervals as the pitch rises, noted by
Helmholtz.

The numerical results reached by us differ, as a whole, consider-
ably from those given by Mayer for interruptional beats in either of
his papers, though the divergence is less than that between the two
series representing his own observations and those of Mrs. Seiler.
In some cases, however, the agreement is very close. Thus, for Ut2
we find the last trace of beats to occur when these are 46 in number.
The number as observed by Mayer is 26, and as observed by Mrs.
Seiler 45. For Ut3 our figure is 70, and Mrs. Seller's is 70 also.

OF ARTS AND SCIENCES. 5

For the other notes the divergence is wide, except for Ut5, for which
our results agree quite well with those obtained by Mayer himself.
These differences may be due to the different way in which the vari-
ations of intensity in the beats progress, to the presence of pitch
variations in interference beats, to the fact that in our method the
musical interval of the beating notes increases as the beats increase
in number, to mere differences in the estimation of the observers,
or to some other less evident causes.

We find that the ratios between the number of beats producing
the greatest harshness at different pitches and the maximum num-
ber of beats discernible at those pitches are as follows (Table III.).
The numbers given are obtained by dividing the former number by
the latter.

TABLE III.

Ut2

UtM

Sol3

Uh

So^

TJh

Mis

0.41

0.37

0.36

0.31

0.30

0.30

0.32

These figures, as a whole, agree very well with the ratio (four
tenths) given by Mayer, although the absolute numbers whose ratios
are taken are quite different from his. Our results also seem to
indicate a clearly marked fall in this ratio as the pitch rises.

A few experiments were made using Professor Mayer's method,
with some slight modifications, in order to observe the judgment of
the same ear upon beats of different kinds. The tuning-fork em-
ployed was kept in vibration continuously by electricity, and the
rotating disk was driven by an electro-motor, which secured great
constancy of speed. We were seriously troubled by the sound made
by the rotating disk, which produced a sort of siren effect as its
openings passed before the aperture of the resonator. For Ut3 the
maximum number of intermittences perceived was 50 per second.
For Uti the number was about 106. These figures are liable to an
error of perhaps two beats, or even a little more for the higher pitch.
Mayer's figures are 47, 78, respectively, for his own observations
on these notes, and 70, 130, for those of Mrs. Seiler. It is clear
that there are very great differences in the sensitiveness of different
ears for the perception of rapid beats.

In another series of experiments, interruptions were produced by
a break-wheel placed in a telephonic circuit with a magneto-telephone
at each end. The sound of a tuning-fork was transmitted through
the line, and any desired number of interruptions could be produced
by varying the rate of rotation of the wheel. Considerable annoy-

6 PROCEEDINGS OF THE AMERICAN ACADEMY

ance was experienced at times from sounds which apparently arose
from microphonic action at the break-wheel. These can probably
be avoided in future experiments by causing the wheel to divert the
current from the receiver periodically, instead of interrupting it.
The limits at which the beats disappeared, with the notes experi-
mented upon, were as follows : TJtA 48, Mit 56, SolA 69. These fig-
ures are the means of a number of observations, and are apparently
true within less than one beat per second. Comparing this kind of
interruptional beat with those given by Mayer's method, the maxi-
mum number perceptible seems to be smaller for the former than
for the latter. This is probably due in part to the greater loudness
of the sounds observed in the latter case, but there is another marked
difference which must exercise an important influence upon the phe-
nomenon under consideration. With the beats produced by the
break-wheel the sound begins and ends almost instantaneously, so
that sharply marked intervals of sound and silence of equal du-
ration succeed each other. One would naturally expect the tele-
phonic beats to be the more distinct of the two, which is not the
case. The subject is one which requires further study as to the
influence of the relative duration of sound and silence in the tele-
phonic method, and of the relative size of the apertures in Mayer's
method.

In the matters which we have thus far discussed in the present
paper, our results are fully in accordance with the theory of conso-
nance proposed by Helmholtz. In some other particulars, however,
we are led to conclude that this theory is incomplete, at least.

Some years ago, in a paper read at the Philadelphia meeting of
the American Association for the Advancement of Science, and of
which an, abstract was published in the Proceedings of that Society
for 1884 (page 113), one of us called attention to the bearing of
certain phenomena of binaural audition upon Helmholtz's theory
as follows : —

" In connection with his study on the effects of beats in causing
dissonance, Helmholtz considers the condition of the vibrating por-
tions of the inner ear as to resonance and damping. In his remarks
on the subject, he assumes that no notes are capable of beating with
each other unless they both affect the same vibrating element of
the inner ear. This view of the matter gives a purely mechanical
action in the ear as the explanation of the physiological phenome-
non of beats.

"In addition to the experiments of Koenig, in which beats were

OF ARTS AND SCIENCES. 7

obtained between notes of very great intervals, there are certain
phenomena of binaural audition which appear to prove that this
view is incorrect, and that rather than, or at least in addition to,
this mechanical interference of vibrations in the ear, there is a more
obscure operation within the sensorium itself. I refer to the fact
that beats may occur when the exciting sounds operate upon different
ears, and also apparently between the after-sensation and the suc-
ceeding sound of mistimed unisons. Whether this last phenomenon
can be observed when the after-sensation results from an impression
made upon the opposite ear to that which is impressed by the suc-
ceeding sound, I do not know; but in view of the fact that two
simultaneous sounds acting upon different ears may beat, I do
not see why this result should not be possible.

''Now if beats arise between the after-sensation and a following
sound, Helmholtz's view can be true only upon the supposition that
the vibrating parts of the inner ear continue in motion as long as
the after-sensation persists ; and that there is no residual sensation
capable of giving beats other than that which persists only as long
as the actual vibration in the ear itself continues. Such a. sup-
position seems quite improbable. Moreover, the phenomenon of
beats in the case of sounds acting simultaneously upon different ears
cannot be explained even upon this supposition. There must "be
some kind of vibration, using this term in the most general sense,
or some kind of alternation of phase or state within the sensorium
itself.

"There is no question as to the fact of the production of beats
under the circumstances last mentioned. I have not only verified
the fact by experiments conducted in the usual manner, but have
also studied the beats produced when a tuning-fork is held close to
one ear and the sound of a second fork, not quite in unison with it,
is transmitted by telephone to the other, taking suitable precautions
that the ear against which the receiving telephone was held was not
affected by the sound of the neighboring fork. Beats were readily
obtained, which grew weaker as the fork was moved away from the
open ear and approached to the ear which was closed by the receiver.
The same result occurred when, instead of mistuned unisons, har-
monic forks were used, which gave beats with the fundamental."

In the experiments just cited, the fact that the fork gave feebler
beats as it was moved towards the ear to which the telephone was
applied seemed clearly to indicate that the beats were not likely to
be due to sounds transmitted through the head from one ear to the

8 PROCEEDINGS OP THE AMERICAN ACADEMY

other, or to the passage of the vibrations through the skull from
the outer air. These experiments did not differ in other respects
from those of previous observers. The beating of the sound per-
sisting in one ear after excitation had ceased with a second sound
falling upon the other ear was, in fact, observed by S. P. Thompson,
in 1881.

The existence of such binaural beats as are under consideration
was noted as early as 1874 by Mach, who assumed that the sound
was conducted from one ear to the other through the bones of the
head. S. P. Thompson has studied the subject very carefully;*
and while he is evidently strongly inclined to believe that the phe-
nomena are due to an interference of sensations not produced by the
same ear, nevertheless he does not appear to consider this as a fact
finally settled beyond all question, although to us his results seem
to leave small room for doubt on the matter.

The important bearing of the existence of binaural beats upon
some parts of Helmholtz's theory of audition does not seem to have
been very fully recognized. This may be because of some question
as to whether each sound did not after all really act upon both ears,
even when apparently applied to one alone. From the nature of the
case, it is very difficult to prove finally that there is no possibility
of such conduction of sound from one ear to the other, but we have
sought to study the phenomena of binaural beats under circum-
stances which render such conduction improbable in the highest
degree. With this end in view, we have repeated most of the ex-
periments of Thompson, and made such additional tests as suggested
themselves to us.

The sounds of two tuning-forks placed in a distant room were
conveyed to the ears telephonically over two separate circuits.
These forks were struck by hammers actuated by electro-magnets
placed in circuits separate from those containing the telephones,
and governed by keys operated by the foot of the observer at the
receiving end of the line. This method was found to be preferable
to running the forks continuously by electro-magnetic means, as
the currents used in the latter method were liable to act directly
upon the transmitting telephone and cause disturbing noises. Very
powerful magneto-telephones were used as transmitters and receivers.
Mii forks were used throughout the experiments, unless otherwise

* Philosophical Magazine, Vol. IV. p. 274 ; Vol. VI. p. 383, Vol. XII. p. 351 ;
Vol. XIII. p. 406.

OF ARTS AND SCIENCES. 9

stated, on account of the remarkable intensity with which their
tones were transmitted, this being approximately the natural tone
of the diaphragm. The singular phenomena of the localization in
the back of the head of the sensation caused by two notes in oppo-
site phases when heard by separate ears, and the apparent wander-
ing of the sensation from one ear to the other in the case of binaural
beats referred to by Thompson, were always clearly recognized.

The method of experimentation precludes any fusion of the two
sounds, except within the head; but to decide whether the beats
arise from an interference of the sensations or from a mechanical
interference in Corti's organ, we must investigate further. We
tried to throw some light on this point by the following experiments.
It is well known that the vibrations of a fork, even when of too
small amplitude to be heard when held opposite the ear itself, can
be made audible by pressing the stem of the fork against the bone of
the skull, or, still better, against the teeth, the latter transmitting
vibrations to the ears better than any other part of the head. A
still more effectual means of making audible very small vibrations is
to close the ear with a bit of beeswax and press the stem of the fork
lightly against the wax. In this case the vibrations are transmit-
ted to the membrana tympani by the small amount of air enclosed
within the meatus, as is clear from the fact that the sound of the fork
is heard on touching the wax long after it ceases to be audible on
touching its stem to the pinna of the ear. Hence in this case there
is no conduction to the middle or inner ear through the bones of the
head. Whatever sound reaches the ear follows the ordinary path
through the meatus to the membrana tynipani. Now we found
that the vibrations of a fork could be heard longer when touched to
the wax in the ear than when held against the teeth. We therefore
took two small tonometer forks making four beats per second, struck
them very gently, and held their stems against the teeth; loud beats
were heard in the ears just as they are ordinarily heard when power-
ful forks are sounded in the air. The forks were then held in this
position until the beats had entirely ceased to be audible, when
they were removed, and the stem of each was touched to the wax
closing the two ears. Instantly the two notes were heard, faintly
but distinctly, in the ears to which they were held, and accompany-
ing them were faint beats seeming to wander in the head from ear
to ear, as is always the case with binaural beats. In trying this
experiment care was taken that no vibration should be imparted to
the fork from a gentle blow given on touching its stem to the wax,

10 PROCEEDINGS OP THE AMERICAN ACADEMY

and it was found that the liability of such an occurrence could be
greatly diminished by covering the end of the stem with a layer
of wax.

To make sure that these beats were not the result of imagina-
tion, we took forks giving four, eight, twelve, and sixteen beats
per second at random, struck them lightly as before, but in this case
held only one of them against the teeth, so as not to know the
number of beats which ought to be produced. When this fork had
ceased to be heard, we touched both forks to the wax in the ears, as
before, and in every case the correct number of beats was at once
heard. The experiment was varied slightly as follows. One ear
only was closed with wax; the other was immersed in a large basin
of water. The experiment was then repeated as above, with the
difference that one fork, instead of being touched to the ear, was
touched to the marble basin, its vibrations being transmitted to the
enclosed ear through the water. The same results were obtained
as before. These experiments were all carried on at night, when
there was not the slightest disturbing vibration in the air. To-
gether with another experiment described below, they lead us to
conclude that aerial vibrations acting upon the ear are not trans-
mitted through the skull or bony parts of the head from one ear to
the other. The experiments cited certainly seem to bear out this
view, at least for tones of feeble intensity. Furthermore, the fact
that differential tones have not been produced binaurally leads us
to believe that it is true generally, even for very intense sounds,
that binaural beats do not result from sound conduction within the
head.

In his experiments Thompson was never able to obtain differen-
tial tones unless the sounds were allowed to mingle before falling
upon the ears. Our experiments fully bear out this result, which
we have verified in the following ways: (1) By listening to TJt±
and Mii forks through the telephones. These notes were trans-
mitted with more than sufficient intensity to give rise to a differ-
ential when heard in the ordinary manner; but with a telephone
placed at each ear, not the faintest trace of such a tone could be
heard. We also reached equally negative results on listening to
M^ with a telephone, and holding an Ut4, Solif or Solz fork close
to the other ear, or on leading their vibrations to the ear through a
long rubber tube. (2) By Thompson's method of carrying the
tones to the ears by means of rubber tubes (in our experiments
about thirty feet long), the forks being struck, one in another

OF ARTS AND SCIENCES. 11

room and the other outside of the window, to prevent their tones
from mixing before reaching the ears. No differential tone could
be heard. We also tried to use Koenig's forks for illustrating
beat-notes, but their very rapid vibrations were so deadened by
the tubing that they could only be heard very faintly. (3) By
the same process as above, with the exception that the ends of the
rubber tube were connected with cylindrical resonators which were
blown as already described. This gave almost deafening tones in
each ear, but not the slightest trace of a differential. But in this
case, as also in (2), if the two tubes were connected to two branches
of a Y tube, and a third rubber tube leading to the ear was con-
nected to the third branch, the differential tone came out at once.
(4) The most striking proof was the following. The ears being
closed with wax, a brass rod about five feet long was held lightly
against the wax in each. When the stems of forks struck by two
assistants were pressed against the farther end of the rods, very
loud tones were heard in the ears, unaccompanied by any differential
tone. If, however, one of the rods was removed from the ear and
pressed tightly against the head, or, better, against the teeth, a loud
differential tone was heard at once in the ear against which the rod
was placed. If both rods were held against the teeth or head, the
differential tone was heard in both ears.

This apparent impossibility of producing differential tones when
the primary tones are caused to actuate separate ears would seem
conclusive of the point under discussion except for the fact that it
might reasonably be argued that, if sound conduction through the
skull occurred from one ear to the other, the vibrations thus con-
ducted might act directly on the inner ear, and not indirectly
through the membrana tympani and chain of bones, in which case
no differential tones should arise, although beats could still take
place in the manner assumed by Helmholtz. But our exjieriment
with the brass rods, described above, shows that such tones are in
fact readily produced when conduction to the ear takes place through
the bones of the head. And if there were any material conduction
of this kind, it certainly seems as if the very loud sounds used
by us would have given evidence of it at least by the occasional
production of differential tones when the sounds actuated separate
ears.

The production of beats without the simultaneous action of the
beating sounds upon the same ear seems, therefore, to be clearly
shown from these facts : (1) Beats are produced by sounds falling

12 PROCEEDINGS OP THE AMERICAN ACADEMY

upon the ears separately even when the greatest precautions are
taken to prevent both from affecting the same ear. (2) Under no
circumstances does it seem to be possible to produce differential
tones by binaural combination, even when the separate tones are
extremely loud. (3) In all cases in which the beating sounds have
apparently acted separately upon the auditory apparatus of each ear,
the singular phenomenon of encephalic localization of the beats has
appeared, while this phenomenon has never been found present
either when the two sounds acted simultaneously upon the same ear
through the auditory canal, or when one of them was manifestly
transmitted to the ear through the bones of the skull.

We are therefore led to the conclusion that the mechanism in
which the interference causing beats takes place, and through the
operations of which we consequently recognize the character of con-
sonant and dissonant intervals, lies, in part at least, beyond the
auditory apparatus of the inner ear. It seems to us clear that notes
may beat when they do not affect the same vibrating elements of
the inner ear, and that we must look to some more profound changes
within the sensorium itself for a complete explanation of the phe-
nomena under consideration.

It may be possible that there are two distinct causes of beating;
one, that suggested by Helmholtz, which wholly or principally
obtains when the two notes act simultaneously upon the same
ear, and the other due to some different and more obscure action
which obtains in the case of binaural beats. In this case quite
different laws as to consonance might hold. The exceeding harsh-
ness of dissonances in binaural audition lends some support to this
view.

Rogers Laboratory or Physics,
May, 1891.

OP ARTS AND SCIENCES. 13

II.

NOTE ON THE DEPENDENCE OF VISCOSITY ON
PRESSURE AND TEMPERATURE.

By Carl Barus.

Presented January 13, 1892.
Table of Contents.

PAGE

1. Historical 13

2. The Material chosen 13

3. Definitions 14

4. Hardness 14

5. Method of Work 14

6. Volume Viscosity 15

7. Viscosit}7 and Pressure. Isotherms 15

PAGE

8. Viscosity and Temperature. Iso-

piestics 16

9. Conditions of Constant Viscosity.

Isometrics 17

10. Isothermal Flow through Tubes . 17

11. Measurement of excessively high

Pressure 18

1. Historical. — In the following paragraphs, I endeavor to give
a preliminary account of what may he called the isotherinals, the
isopiestics, and the isometrics with respect to viscosity. Notwith-
standing the great geological importance* of these relations, nobody
has as yet attempted to represent them systematically.

2. The Material chosen. — In order to obtain pronounced results
for the effect of pressure on viscosity, substances must be selected
on which temperature has a similarly obvious effect. For, in
addition to the direct access to the molecule which is beyond the
reach of pressure, temperature has the same marked influence on
the expansion mechanism per unit of volume increment as the
other agency. Hence liquids like marine glue, pitch, etc., which
change continuously from solid to liquid, and in which this change
takes place at an enormously rapid rate and is complete within
relatively few degrees, are especially available for the present
investigation.

The following data refer to marine glue. Viscosity is considered
as a physical quality, and apart from such chemical considerations
as are introduced in passing from one body to another.

* This will be indicated by Mr. Clarence King, for whom this work was done.

14 PROCEEDINGS OP THE AMERICAN ACADEMY

3. Definitions. — In my paper* on the absolute viscosity of the
three states of aggregation, I defined a fluid (liquid or gas) as a
body which, under constant conditions of pressure, temperature,
and strain, shows constant viscosity as to time. In a solid, coeteris
paribus, viscosity markedly increases with the time during which
stress is brought to bear. The molecular instabilities of a liquid,
therefore, are supplied at the same rate in which they are used in
promoting viscous motion. In a solid they are used more rapidly
than the small rate of continuous supply.

The point of essential concern in these definitions is the con-
stancy of stress, and its value below a certain critical datum. For
instance, if in a solid stress be increased at the (small) rate necessary
to insure a constant supply of instabilities, then solid viscosity will
also be constant, and I am by no means sure that in such a case f
yield points would eventually present themselves as breaks in the
continuity of the solid view.

On the other hand stress may be conceived to increase so fast,
that even a liquid fails to present sufficient instabilities for truly
viscous motion. The elasticity and brittleness of many viscous
liquids, especially at low temperatures, is a case in point.

4. Hardness. — Throughout my work on viscosity, X I have ad-
verted to the association of viscosity with zero forces acting for
infinite times, and of hardness with infinite forces (relatively) act-
ing for zero times, and have adduced many new examples showing
the utter distinctiveness of these two properties. The subject of
hardness has, however, recently taken more definite shape in the
researches of Auerbach,§ based on a principle due to Hertz. ||
According to these observers, hardness is an expression for the
elastic limits of a body in case of contact between its plane sur-
face and the curved surface of some other (harder) body. Hard-
ness so defined admits of absolute measurement in terms of dynes
per square centimeter.

5. Method of Work. — In all experiments like the present, one
cannot be too careful to preconsider the conditions under which the
results are obtained; for one is only too apt to attribute an absence

* Phil. Mag. (5), Vol. XXIX. p. 337, 1890. Cf. p. 354.
t Cf. Am. Journal (3), Vol. XXXIV. p. 19, 1887.

| Phil. Mag. (5), Vol. XXVI. p. 210, 1888. Cf. Bull. U. S. Geolog. Survey,
No 73, pp. 42-44, 97, 98, 1891.

§ Auerbach, Wied. Ann., Vol. XLIII. p. 61, 1891.
II Hertz, Crelle's Journal, Vol. XCVI. p. 156, 1882.

OP ARTS AND SCIENCES. 15

of flow to the effect of pressure on viscosity, when the real cause is
to be found in the geometry of the apparatus employed. I have
therefore availed myself of transpiration methods, since the theory
of the experiments is in this case very fully given.*

The marine glue, § 2, was forced out of a sufficiently large reser-
voir, through tubes of steel about 10 cm. long, and 0.5 to 1cm. in
diameter. Pressures as high as 2,000 atm. were applied at the
reservoir, by aid of my screw compressor.! Temperatures between
10° and 30° were kept constant by a suitable water bath. Through-
out the work the flow was so excessively slow (amounting to an
advance of only a few millimeters per hour), that Poiseuille's law
was at once applicable. The only considerable source of error in
the work is the occurrence of more or less incidental slipping.
However, inasmuch as the outflow of marine glue is capped by a
rounded surface, it follows that the flow is most marked at the axis
of the tube compatibly with the theory of the experiment.

6. Volume Viscosity. — At the end of stated intervals of time
(usually hours), the small cylinders of marine glue which had
exuded were cut off with a sharp knife, and weighed. Now it was
curious to note that these cylinders, left to themselves for about a
day, showed a gradual and marked deformation, such that the
originally plane bottom or surface of section eventually expanded
into a symmetrical projecting conoid, with an acute apex angle of
less than 45°. I take this to be an example of volume viscosity.
The restitution of volume is greatest in the axis of the cylinder
where the flow is a maximum, and where the matter has been
crowded into the smallest space. As a whole, the experiment is
somewhat puzzling, for it points to the occurrence of a notable
amount of slowly reacting elasticity even in this truly viscous
solid. Indeed, as time went on, a re-entrant conoid, correspond-
ing to the projecting cone just described, gradually dimpled the
second of the two surfaces of section. What is here indicated,
therefore, is probably a surface of flow.

7. Viscosity and Pressure. Isotherms. — Table I. gives a sum-
mary of my chief results. The table is one of double entry, and
the data contained show the absolute viscosity (77) of marine glue
at the stated temperatures and pressures, in terms of one billion

* In addition to the well known work of Poiseuille, of. Hagenbach, Pogg.
Ann., Vol. CIX. p. 385, 1860; Osborne Reynolds, Phil. Trans., Vol. III., 1883,
p. 935 ; Wilberforce, Phil. Mag. (5), Vol. XXXI. p. 407, 1891.

t These Proceedings, Vol. XXV. p. 93, 1890.

16

PROCEEDINGS OP THE AMERICAN ACADEMY

g/cs units. The pressure excess is the difference of pressures at
the two ends of the tube.

TABLE I. — Mean Values of tj/109 for Marine Glue.

Ap = Pressure Excess =

100 atm.

300 atm.

1000 atm.

1500 atm.

2000 atm.

Temperature = 8.5°

—

—

> 30 000*

—

> 60 000 *

= 18.3°

(2.5)

—

8.30

12.0

15.2

= 22.5°

—

—

1.12

—

2.2

= 30.5°

.065

.073

—

—

—

Rates at

85^

18.3d

22.5°

30 5°

10-9 x Al] /1A|)-

—

.0137

.00220

a-A-f)lna X ^ A;j —

—

.0091

.020

In constructing the rate of change of viscosity with pressure,
I assumed that the whole thread transpired at the mean pressure at
the two ends of the steel tube; or since the pressure at the open end
is zero, at half the pressure excess. Furthermore, that

VP = Vo 0- + ap) = r]0 (1 + £ a <\p).

If therefore A r) be the increment of viscosity corresponding to
the pressure ^ Aj?, the final data of Table I. (rates) are at once
intelligible.

In view of the occurrence of the arbitrary variable r]0, it is hardly
probable that a would be independent of temperature. If reference
were made to some other pressure, viz. a' = (rj — rj0) / r}P) the val-
ues of a' approach each other in proportion as P is larger. Thus,
for P= 1000 atm., a' = .009 at 18°.3 and a' = .010 at 22°. 5. The
point of immediate importance here, however, is that in proportion
as the viscosity of a body increases with fall of temperature, its
isothermal rate of increase with pressure also increases; and that
the rate of increase in the latter instance is a coefficient as re-
markably large as a = .01 to .02.

8. Viscosity and Temperature. Isopiestics. — Table I. also ena-
bles me to construct the approximate isopiestics for A p = 0, 500,

* No flow perceptible after five hours, in case of a tube 10 cm. long and 1 cm.
in diameter.

OF ARTS AND SCIENCES.

17

1000, and 2000 atm. These loci are distinctly curved, showing
that viscosity decreases at an accelerated rate with rise of tem-
perature.

9. Conditions of Constant Viscosity. Isometrics. — In order, how-
ever, to compare the relative effects of temperature and pressure, it
is necessary to map out the lines of equal viscosity for marine glue.
I endeavored to do this hy constructing Table I. graphically; thus
I attained the data of Table II., where Ap is the pressure excess
corresponding to the temperature 0, for the case in which the vis-
cosity r) has the value given at the head of the table.

TABLE II. — Isometrics as regards Viscosity for Marine Glue.

1 =

i x io9

r, = 2 x 109

T) = ,

iX 109

t, = 5 X 103

Ap

0

Ap

e

Ap

0

Ap

0

atm.
0

°C.
19.1

atm.
0

°c.
17.7

atm.
0

°c.

16.8

atm.
0

°C.

500

21.7

500

20.4

500

19.6

500

18.3

1000

22.8

1000

21.4

1000

20.6

1000

19.4

2000

24.3

2000

22.7

2000

21.8

2000

20.5

$ =

.0030

0 =

.0026

0 =

.0024

0 =

.0022

There are thus given a family of lines of decreasing curvature.
Supposing them to be eventually more nearly linear I have con-
structed fi = k.6 l\ Ap (where A 6 and ^ A p are the correspond-
ing increments of temperature and pressure for constant viscosity)
for the region between Aj) = 1000 and 2000 atm. See Table II.
These values, crude as they are, have an important geological bear-
ing on the fluidity of magmas. I infer that in a field of high pres-
sure as small a rise of temperature as 1° C. will quite wipe out
the increment of viscosity due to a pressure as large as 400 atmos-
pheres.

10. Isothermal Flow through Tubes. — Let there be given a tube
of length I and radius p. Let t] = -q0 (1 + a p) be the viscosity of
the viscous liquid forced through it by the pressure excess A p = 2 p
(so that there is no pressure at one end of the tube) and at the con-
stant temperature 6. The length A of the cylinder of fluid issuing
per unit of time (t) will be

vol. xxvn. (n. s. xix.) 2

18 PROCEEDINGS OF THE AMERICAN ACADEMY

A App2

t ''"' 8lVo(l + $aAp)'

Hence the maximum flow will occur when A p = — 2 / a, or, as
negative pressures are excluded, the function A / t is of a kind con-
tinually increasing with A p.

11. Measurement of excessively high Pressures. — In view of this
property of A / 1, it is worth inquiring in how far the transpiration
method is available for high pressure measurement, when all other
means fail.

Take for example marine glue, and a tube r\ inch in diameter
and 1 inch long. Then the mass m of marine glue which at 18°. 3
would exude per hour is given in Table III.

TABLE III. — Transpiration of Marine Glue, per Hour, at 18°.3 C.

I = 2.5cm. p = .08 cm. tj = 1.5 (1 + .009J Ap) x 109.

Ap = 1000, 5000, 10000, 15000, 20000 atra.

m X 106 = 4232, 4949, 5060, 5096, 5115 grams.

Thus it appears that whereas a hole T'ff inch in diameter may be
efficiently sealed by marine glue at 18°. 3 C, pressure measurement
by aid of the exuding mass is impossible above 10,000 atm., whereas
even between 5,000 atm. and 10,000 atm. the method is insensitive.
To use a method like the present for very high pressure measure-
ment, a substance of smaller pressure coefficient must therefore be
sought, if such a one with other necessary qualities, exists. It is
with the object of searching for such a body, as well as of finding
the maximum of hydrostatic pressure attainable in the laboratory,
that I had a tinned screw and socket constructed,* and hope to be
able to report the results of my work at an early opportunity.

* These Proceedings, Vol. XXV. pp. 94, 108, 1890.

Physical Laboratory U. S. Geological Survey.

OF ARTS AND SCIENCES. 19

III.

WHAT ELECTRICITY IS: ILLUSTRATED BY SOME
NEW EXPERIMENTS.

By W. W. Jacques.

Presented January 13, 1892.

Electricity is, to all of us, more or less surrounded with an
atmosphere of mystery.

When we speak of Light, or Sound, or Heat, we feel that we are
dealing with familiar things, — things so familiar to our every-day
life that it seems useless to try to define or describe them. Every-
day the sunlight fills all space; it dazzles our eyes; it falls upon
the objects around us, and makes them visible ; and though
through the evening, when the sun is gone, we substitute for a
while a gas flame, or a candle, or an electric light, we have then
through the day had so much of it that at night we are glad to be
rid of it, and have darkness for our hours of repose.

So, too, from babyhood to old age, all day long and every day,
we are listening to one or another sound, whether the voices of
friends, or the busy hum of city life, or the delights of music, or
the ticking of the clock at night. Indeed, so constantly are our
ears filled with sounds, that, when we go alone on to a high moun-
tain, or a desert plain, where there are no trees to rustle with the
wind, the silence is painful and oppressive and awful.

Heat, too, is equally familiar, perhaps even more so : for what
is more familiar than the warmth of sunshine? And is not the
fireside the very centre, as well as emblem, of our home?

When, however, we speak of that other great force of nature,
Electricity, we feel that we are departing from familiar ground. It
is shrouded in mystery; it is something we cannot see, or hear, or
feel, — something we cannot easily describe or define. We speak
of it in the same breath with spirits and with ghosts. The rea-
son, I take it, is because the human body has no organ especially
adapted to recognize electrical phenomena. While the eye re-
ceives the ray of light, the ear the ray of sound, and any part of

20 PROCEEDINGS OF THE AMERICAN ACADEMY

the surface of the body feels the heat, the presence of electricity
cannot he detected by any of our senses. Electricity cannot be
seen, or heard, or felt; it is tasteless and odorless.

Subjectively considered, then, electricity eludes our grasp.

Objectively, however, electricity is as familiar to us as light, or
sound, or heat. Its phenomena have been as carefully studied,
and its laws are as accurately known.

Let us for a moment recall the physical explanation of light and
sound. Let us picture to the eye of the imagination the mechanics
of a ray of light.

When we stand out of doors on a cloudless night and look above
us, we see a multitude of stars. The telescope tells us that some
of these are suns, some are moons, and some are other worlds than
ours.

The nearest of them is distant millions of miles, and yet we can
see them. There is a chain of something linking the star at which
we are gazing to the eye. This chain we call, familiarly, a ray of
light. Physicists tell us that along the pathway from the star to
our eyes there are chasing each other with enormous speed a mul-
titude of waves of light.

If we turn our eyes to another star, it too sends to our eyes its
waves of light. If we go to a distant part of the earth, the same
stars send rays of light to us there. And so we find that each of
the multitude of stars is radiating ceaselessly in all directions mul-
titudes of waves of light.

Between us and the stars, and between the stars extending
everywhere through visible space, is the medium that transmits
these waves, crossed and intercrossed continually with countless
waves of light, — a medium rarer than the rarest gas, — the medium
that is still left in space when we remove from it all solids and
liquids and gases, the ether.

Objectively considered, then, light is a wave motion of the ether
that everywhere surrounds us and fills all space. By a similar
wave motion, but in a coarser medium, the air, sound is trans-
mitted from place to place.

By means of his vocal organs, a public speaker moulds the cur-
rent of air that issues from his lungs into waves of sound. These
waves of sound are radiated in all directions, and fall upon the
various listeners' ears.

Something analogous takes place when we drop a pebble on to
the surface of a placid lake. From this centre of disturbance,

OF ARTS AND SCIENCES. 21

waves of water are radiated in all directions until they reach the
shore. Waves are likewise radiated downward to the bottom of
the lake, and fishes have organs, like our ears, that enable them to
take cognizance of these vibrations.

In the case of waves of water, or waves of sound, or waves of
light, we know there is no bodily transference of a particle of
water, or air, or ether, from the centre of disturbance to the shore,
or ear, or eye. Each particle moves at the most only through a
minute fraction'of an inch; but each pushes the next, and this the
next, so that motion, and not matter, is what is transmitted to a
distance. Indeed, this propagation of motion, in contradistinction
to propagation of matter, is the essential characteristic of wave
motion.

Who has not seen a wave pass over a field of grain? Each par-
ticle bows its head but for a few inches, yet the wave passes on to
the utmost limit of the field.

Sound, then, is a wave motion transmitted through the air.
Light is a wave motion transmitted through the ether. But both
of these media are also capable of having set up in them currents
in which there is an actual bodily transference of the medium from
place to place through considerable distance.

In the case of air, we call this motion the wind. In the case of
the ether, I propose to show that it is a current of electricity.

As wind is the bodily forward motion of the medium whose
vibratory motion we call sound, so a current of electricity is the
bodily forward motion of the medium whose vibratory motion we
call light.

A current of electricity is a breeze of light.

We may, perhaps, best get a realistic conception of electric cur-
rents, whether flowing through open space, or confined to a spe-
cially provided metallic conducting path, by first picturing to
ourselves the phenomena of air currents, with which we are more
familiar, and then mentally transferring these phenomena from the
air to the more subtle medium, the ether. The analogies are very
striking, and will materially aid the imagination in picturing
electrical phenomena.

In the islands of the Pacific Ocean there is almost always a
breeze, either from the land to the water, or from the water to the
land. In the daytime the island is heated by the sun, its air is
rarefied and rises, and the cooler breeze rushes in from the ocean
to take its place. At night the island cools, the air descends, and

22 PROCEEDINGS OP THE AMERICAN ACADEM5T

an outward breeze is produced. There is always a breeze from an
area where the air is condensed, and towards an area where it is
rarefied. This local condensation and rarefaction of the air are the
cause of breezes and winds and hurricanes. The maps issued by
our weather bureau show areas of high and areas of low barometer,
and the direction of the wind is always from the one to the other.

If, instead of allowing the wind to blow freely through space, we
confine it to a narrow channel, — if, for instance, we produce an air
pressure at one end of a long iron pipe, we get through the pipe a
strong current of air, — as, for example, in pneumatic tubes, in
which the current of air carries along small carriages, in the tin
pipes used to convey the hot-air currents from our furnaces to the
registers, and in the pipes used for distributing illuminating gas
from the central gasometer to the houses about the city where it is
burned.

The wind blowing through space is made evident to our eyes
by its scattering of a handful of dry leaves, or dust, or bits of
paper. It bows and bends the branches of the trees. A candle
flame exposed to it is distorted, or instantly blown out. Its direc-
tion is more accurately indicated by the familiar weather-vane, and
its strength is measured, if we will, by the anemometer.

As with the wind of nature, so too with the electric wind. If
we substitute for our Pacific island a metal ball suspended in mid-
air by a silken cord, and let the ocean be represented by the sur-
rounding atmosphere on a moist day, and produce upon the ball an
area of electric condensation, or, as an electrician would say, a posi-
tive electric change, we shall have an electric breeze blowing out-
ward in all directions, which will last so long as the electrification
of the ball is above that of the surrounding air. This may be made
evident to the eye by placing upon the ball a handful of bits of
paper, or dry leaves, or dust, any of which will be instantly blown
away and dissipated in all directions. If a lighted candle be
brought near the ball, its flame will be bent by the breeze, and
possibly be blown out.

If instead of allowing this electric wind to blow away in all
directions we confine it to a narrow path, — if, for instance, we con-
nect the ball to the earth by a metallic wire, — we get through
the wire a strong current of electricity, whose direction may be
determined by the electric weather wave, a magnetic needle, and
whose strength may be measured, not with the anemometer, but
by the galvanometer.

OF ARTS AND SCIENCES. 23

We may conceive of this electric wind as a breeze of the ether:
the proof of the identity will be given later.

It is in currents flowing along metallic wires that the phenomena
of electricity have been most carefully studied, and it is the phe-
nomena of such currents that have therefore been for the most part
utilized in electrical inventions.

Nature's wind is used to waft our ships across the seas, and it is
perhaps not a wild idea to conceive of electric repulsion utilized to
support and propel heavily laden air ships through the space above
our heads; but it is with electric phenomena as they have been
investigated and utilized up to the present time that we have to
deal in this article, and this, as we have seen, means the phenom-
ena of electric currents flowing through metallic wires.

What are some of these phenomena ?

Electricity — or what we shall soon see is the same thing, a cur-
rent of ether — passes readily through a copper wire. To the ether
current, the wire is hollow; in electrical terms, it is a good con-
ductor. It also passes quite readily through an iron wire, but not
so readily as through copper. It passes still less readily through
a wire of carbon. It passes more readily through a large wire than
through a small wire. In all wires, there is more or less ethereal
friction or electric resistance.

In virtue of this ethereal friction or electric resistance, the cur-
rent heats the wire through which it passes, — of course heating a
small wire more than a large one, and heating an iron wire more
than one of copper, and a carbon wire most of all. We see this in
our household system of electric lighting. The current passes
from the central station and throughout our houses to the lamps,
over comparatively large wires of copper, which it warms only
slightly; but coming to the lamps, it passes through a fine wire
of carbon, in which the friction and consequent heating is so great
that the filament becomes white hot; and were it not contained in
a glass globe, from which the air has been removed, it would take
fire and disappear.

Again, an electric current flowing in a wire coiled around a bar
of iron converts the bar of iron into a magnet, so that it may at-
tract an iron armature placed near its end, and thus do mechanical
work. The converse of this is equally true, and if we move an
iron armature to or from the end of an iron bar around which a
wire is coiled, an electric current will be set up in the same coil,
and by means of the connecting wires may be carried to a distance

24 PROCEEDINGS OF THE AMERICAN ACADEMY

and utilized. On this latter principle depends the dynamo ma-
chine, which furnishes electricity to be used for light or power.
On the former depends the electric motor that propels our street
cars, and furnishes power to many of our industries.

Again, the electric current flows through wires with enormous
velocity, and consequently it offers an excellent vehicle for the
rapid communication of intelligence, — for telegraphy. A tele-
egraph wire between two cities is merely a path through which the
current may readily flow. At one end is a reservoir of electricity.
The "key" is a device by which electricity may be allowed to
flow into the line. By allowing small quantities of electricity to
flow into the line at intervals of time in accordance with a pre-
arranged code, and noting at their distant end their arrival, we
may communicate any ideas that are capable of being expressed in
such a code.

The arrival of these little currents of ether may be manifested
to the eye in various ways. In the so-called needle telegraph, the
current passing by a magnetic needle causes it to point in a given
direction, just as the wind passing a weather-vane causes it to poiut
in a given direction.

If it were possible to have on one hill-top a reservoir of air un-
der pressure, or wind, and a key by which small puffs of air could
be let out at intervals in accordance with a pre-arranged code, and
on a neighboring hill a weather-vane, we might thus have a wind
telegraph operated exactly as is the electric telegraph. But such
a telegraph would be slow and cumbersome in operation, and is not
likely to come into general use.

There is one other phenomenon on which I desire to dwell a
moment, — a phenomenon of great importance, as it furnishes the
first proof of the identity of electricity and the ether.

Suppose we have an ordinary telegraph wire in which there is a
steady current flowing. Suppose ten feet away from this wire, and
entirely disconnected from it, we arrange a short wire with any
suitable means of detecting an electric current in it, should such
a current exist. So long as the current in the first wire flows
steadily on, there will be no current in the secondary wire. If,
however, the current in the first wire be broken uj) into rapid
pulsations, say 100 per second, by rapidly opening and closing the
circuit we shall find in the secondary wire short pulsating cur-
rents occurring with the same frequency. How does this action
take place ? How are the impulses transmitted across apparently

OP ARTS AND SCIENCES. 25

unoccupied space ? The only conductor between them is possibly
the moist air; but the same phenomenon takes place if the air be
dry, or even if it be entirely removed. The only remaining ex-
planation is that the pulsations are carried from one wire to the
other by means of the intervening ether which we know fills all
space. We shall see in a moment that the pulsations are trans-
mitted by means of a wave motion of the ether from the one wire
to the other.

Meanwhile, let us look at the analogy of this phenomenon as it
takes place in a current of air.

Suppose we have a pipe in which there is a steady current of air
flowing. Suppose ten feet away we place our ear. So long as the
current of air flows steadily on, no sound will be heard. If, how-
ever, the current in the pipe be broken up into rapid pulsations,
say 100 per second, by rapidly opening and closing its end, which
may be done by means of a reed such as is used in organs, the pipe
will radiate in all directions waves of musical sound of a pitch
due to 100 vibrations per second, and this sound will of course
be heard by the ear. In this case we have a current of air, by
rapid interruptions, converted into waves in the air, or sound.

Analogy indicates that, in the former case, we had a current of
ether (or electricity), by rapid interruptions, converted into waves
in the ether (or electrical waves). But we must have stronger
proof than the indications of analogy, and it is readily forthcoming.

If the interrupted current in the wire radiates ether waves,
these ether waves are really nothing more nor less than waves of
light. Unfortunately, the eye only detects waves of light that
are a small fraction of an inch in length, while the waves radiated
from the most rapidly interrupted electric current are many inches
in length. Nevertheless, the complete identity of waves radiated
from an interrupted electric current and from a source of light
has been confirmed by the study and identification of many of
their phenomena, first by Maxwell, and later by Hertz ; the
most striking proof being that waves radiated from an electric
wire are propagated through space with a velocity of 300,000,000
meters per second, which is the same as the velocitjr of light.

So far as wave motions are concerned, therefore, those radiated
from an electric wire are just as much ether waves as those radiated
from the sun, or any other source of light.

It remains now to show the identity of the electric current and
a current of ether. For this I invite your attention to some exper-

26 PROCEEDINGS OF THE AMERICAN ACADEMY

iments of my own, that seem to me to go far towards establishing
this identity.

If we can find somewhere in nature a breeze of ether blowing
with the necessarily enormous velocity freely through space, and
show that it exhibits both qualitatively and quantitatively the
same properties as an electric current, the simplest possible suppo-
sition that we can make is that they are identical.

Now, the earth in its daily journey round the sun rushes
through the ether that fills all space with enormous velocity, and
to the observer on the surface of the earth this is the same thing
as if the earth were at rest and the ether flowed by with this same
velocity. Just as the observer on the deck of a swift steamship at
sea feels the same breeze, whether the ship moves forward with a
speed of twenty miles an hour through a calm atmosphere, or the
breeze blows with a velocity of twenty miles an hour by the steam-
ship when at anchor.

Now, our problem is to detect and measure this ether breeze, and
show that qualitatively and quantitatively it possesses the proper-
ties of a current of electricity. This I have done in the following
way.

Before us stands a very sensitive balance, capable of detecting a
variation in weight of one part in a million. I have replaced the
scale-pans with thin disks of brass, ten centimeters in diameter.
Above and below each disk, and supported from the floor of the
balance by glass legs, are other similar disks of brass. The two
suspended disks are, of course, free to move up and down, but
remain at rest so long as the equilibrium of the balance is
undisturbed.

The remaining four disks are rigidly fixed, excepting as each
can be raised or lowered by a delicate micrometer screw. For con-
venience I will designate the right-hand disks Rt, Rm, and Rb,
indicating respectively right-hand top, right-hand middle, and
right-hand bottom. Similarly, I will designate the left-hand
disks Lt, Lm, and Lb. By means of a suitable battery I may
electrify airv of these plates, either positively or negatively.

Suppose, now, I electrify the beam of the balance, and conse-
quently plates Rm and Lm positively. If the distances between
plates are in all cases the same, the index will remain at rest. If
it deflects, we know the distances are somewhere unequal, and
must be adjusted by means of the micrometer, until there is no
deflection.

OP ARTS AND SCIENCES. 27

If, now, I electrify Bt negatively, it will attract and lift Bm,
and the index will move to the right.

If, however, I at the same time electrify Lb positively, it will
tend to repel and lift Lm, and, as the repulsive lifting of Lm is
equal to the attractive lifting of Bm, the index will remain at
rest. That is, an attraction between Bt and Bm is balanced by a
repulsion- between Lb and Lm.

If, now, I suddenly change the electrification of the beam of the
balance, and consequently of the plates Bm and Lm, to negative,
we have a repulsion between Bt and Bm, balanced by an attraction
between Lb and Lm.

Now, it can be shown by purely mathematical reasoning from
electric phenomena, (see Maxwell's Electricity and Magnetism,
Chap. XIX.,) that an ether current flowing between two positively
electrified plates would, provided it possessed the electro-magnetic
properties of a current of electricity, diminish their repulsion. If
it flowed with the velocity of light, and had quantitatively, as well
as qualitatively, the electro-magnetic properties of a current of elec-
tricity, it would just neutralize the repulsion.

If, on the other hand, it passed between two plates, one of which
was charged positively and the other negatively, it would just
double their attraction.

If, instead of moving with the velocity of light, 300,000,000
meters per second, it moved only Yulixm as fast, or 30,000 meters
per second, the repulsion between similarly electrified plates would
be diminished by one part in ten thousand, and the attraction
between oppositely electrified plates increased one part in ten
thousand.

Now, it can be further shown from purely astronomical measure-
ments that our balance is, on the 22d of December at noon, carried
through space with a velocity of 30,000 meters per second.

Observations made at noon on that day, then, ought to show the
index of the balance one side of the position of equilibrium when
the movable plates are electrified positively, and the other side
when electrified negatively. The difference should indicate a total
change of force of one part in twenty-five hundred.

This deflection of g^Vo ^s tna^ due simply to the rotation of the
earth around the sun. That due to the rotation of the earth about
its axis is too small to note. But the whole solar system is moving
towards Hercules with a velocity of 8,000 meters per second.

On the 22d of March this velocity would have to be added to the

28 PROCEEDINGS OP THE AMERICAN ACADEMY

velocity of the earth in its orbit, and on the 21st of September
subtracted. On the 22d of December it would have no effect. Our
deflection on March 22d, then, should be about SDVoJ on December
22d, ^o o ; and on September 21st, 27W

Of course, in actually taking observations, it is necessary to use
all six of the plates variously grouped and variously electrified, in
order to get rid of accidental phenomena.

Even then the accidental phenomena frequently mask that for
which we are searching, and it is only from the discussion of a con-
siderable series of observations that results of value are obtained.

I began my observations last September, and have continued
them at intervals since. The results observed are of the order of
magnitude predicted, and vary, as expected, with the season of
the year.

If, continued until next September, the cycle is complete, I
shall feel even more sure of having discovered the phenomenon for
which I am searching, and of showing that the motion of the ether
possesses, both qualitatively and quantitatively, the properties of
an electric current, — that an electric current is a bodily f one ard
motion, of that same ether whose undulations we call light.

OF ARTS AND SCIENCES. 29

IV.

CONTRIBUTIONS FROM THE CRYPTOGAMIC LABORATORY
OF HARVARD UNIVERSITY.

XVII. — FURTHER ADDITIONS TO THE NORTH AMER-
ICAN SPECIES OF LABOULBENIACEiE.

By Roland Thaxter.

Presented by W. G. Farlow, March 9, 1892.

The present paper includes the additions which have been made
during the season of 1891 to the previously recorded species of
North American Laboulbeniacete, a small number only of new-
forms being reserved for later description from lack of sufficient
material. Three new genera are represented, — Ceratomyces by
two species, Corethromyces and Acanthomyces each by a single
species. The genus Heimatomyces, formerly including a single
European form, contributes ten species, nine of them new while,
lastly, the genus Laboulbenia adds sixteen species, thirteen of
which are undescribed. In all thirty species, by which the sum
total of American forms is increased to forty-nine. The material
examined was collected by the writer partly in Maine, partly in
Connecticut; while very important additions have also been re-
ceived through the kindness of correspondents, from whom the
communication of hosts likely to be infested has been solicited.
For such courtesy the writer is especially indebted to Mr. Theo.
Pergande, who has sent Coleoptera collected in the vicinity of
"Washington, D. C, and to Miss A. M. Parker, for numerous
interesting specimens taken at Slaughter, Washington. Mr. J.
M. Aldrich has also kindly sent specimens from South Dakota,
and Mr. Samuel Henshaw has determined the greater part of the
insect hosts. For all these favors, the writer desires to express his
grateful acknowledgments.

The contribution of aquatic forms is of especial interest, the
genus Ceratomyces forming a distinct departure from previously
described generic types. The considerable addition, also, to the

30 PROCEEDINGS OF THE AMERICAN ACADEMY

species of Heimatomyces serves accurately to define the characters
of this genus, which proves to have been based by Peyritsch almost
wholly on specific characters; while it is more than probable that
the same author's genus Chitonomyces is also similarly based, and
should be united with Heimatomyces. No specimens of the former
genus being accessible, and the published figures leaving much un-
certainty as to its true nature, the name Heimatomyces has been
chosen to distinguish the American forms, their generic identity
with H. paradoxus being unquestionable. The type of the genus
is a very simple one, and may be characterized as follows.

HEIMATOMYCES, Peyritsch.

Receptacle consisting of a basal and terminal portion : the basal
including five cells, the two lower superposed, the three upper
small and forming the base of the perithecium: the terminal por-
tion including four cells more or less connected laterally with the
perithecium, the terminal cell always free, bearing at its rounded
apex a single simple thread-like appendage: the subterminal cell
free from or connected on its inner side with the two remaining
cells, the upper of which gives rise, from the angle made by the
inner wall of the perithecium, to several simple thread-like eva-
nescent appendages (trichogyne and antheridia?). Perithecium
simple or appendiculate, symmetrical or asymmetrical. Asci sub-
lenticular, 4-sporic, spores fusiform or subfusiform, septate.

In a single species (H. Halipli) the middle of the three cells
which usually form the base of the perithecium is enlarged, and
extends the whole width of the receptacle, the base of which thus
consists of three superposed cells. The terminal and subterminal
cells of the receptacle may be elongated or modified; but the total
number and general relative position of the cells seem to be very
constant. In only two species, H. paradoxus and H. appendicu-
latus, is the perithecium modified by an outgrowth from one of its
cells.

Heimatomyces simplex, nov. sp.

Pale yellowish or faintly brownish. Perithecium rather slender,
continuing the strong curve of the receptacle evenly outward to its
rather coarse blunt apex. Basal cell of the receptacle much longer
than the flattened sub-basal cell, the septum between the two often
obsolete : terminal cell bell-shaped, small. Spores 26 X 11 /m.

OP ARTS AND SCIENCES. 81

Perithecia 55-60 X 11-12^. Length of receptacle 75 jx. Basal
cell 15 X 7.5/1. Total length 90-100 p.

On LaccophUus maculosus, Hydroporus spurius, etc., Connecticut.

A very common species, occurring in considerable numbers on
the elytra of the host, possessing the simple typical structure of
the genus, and distinguished by its evenly curved habit, blunt
perithecium, and uniform color.

Heimatomtces htalinus, nov. sp.

Hyaline or very faintly tinged with yellowish brown. Perithe-
cium large, at first hunched externally, and bent inward near the
apex, becoming nearly straight, tapering to the rather small apex,
which is bent somewhat abruptly outwards at maturity. Basal
and sub-basal cells of receptacle broad, nearly equal, or the basal
twice as long as the sub-basal, the two separated by a well defined
septum. Spores 8 X 2.5 /*. Perithecia 75-90 X 20 /x. Total
length to tip of perithecium 110-120 fx.

On LaccophUus maculosus, Connecticut.

Differing from the last in its larger size, and stouter straight
perithecium, as well as in minor points. It occurs only on the
posterior legs of its host.

Heimatomtces affinis, nov. sp.

Rather strongly suffused with yellowish brown. Perithecia
commonly slightly curved inwards, or nearly straight, the tips
often slightly bent outwards. Basal cell of receptacle large, sub-
triangular, suffused laterally and terminally with deep black-
brown : sub-basal cell very flat ; terminal cell small, its axis bent
strongly inwards. Spores 50-55 X 3 jx. Perithecia 100-110 X
30 fi. Basal and sub-basal cells of receptacle 40—15 fi. Total
length to tip of perithecium 150-170 fx.

On LaccophUus maculosus and Hydroporus sp., Connecticut.

Nearly allied to H. hyalinus, from which it may be separated
by its larger size and suffused basal cell. It occurs at the apex of
the right elytron.

Heimatomtces appendiculatus, nov. sp.

Becoming faintly brownish. Perithecium tapering to a rather
sharp apex, curved strongly outwards, hunched externally (often
distorted by twisting), and bearing a straight, sub-clavate, one-
celled, brownish appendage arising externally below the apex.

32 PROCEEDINGS OF THE AMERICAN ACADEMY

Basal cell of the receptacle rather narrow, more than twice as long
as the squarish sub-basal cell. Spores 32 X 3 //.. Perithecia 55 X
15 fx to 75 X 22 /jl. Basal and sub-basal cells 30-45 /* in length.
Perithecial appendage 30-33 X 4 [x. Total length to tip of peri-
thecium 100-130 /x. Greatest breadth 30-36 lk.

On Laccophilus macidosus, Connecticut.

A rare species, confined to the anterior pair of legs of its host,
and distinguished at once by its clavate perithecial appendage
which corresponds to the similar horn-like projection from the
perithecium of H. paradoxus.

Heimatomyces paradoxus, Peyr.

This species occurs not uncommonly on the edge of the left
elytron of Laccophilus maculosus in company with H. marjinatus.
The ascogenic area is so placed that the asci and spores are much
distorted at maturity; but the latter do not appear to have the
peculiar shape represented by Peyritsch.

Heimatomyces Halipli, nov. sp.

Strongly suffused with yellowish brown. Perithecia inflated,
more strongly externally, rounded to the papillate tip. Base of
receptacle composed of three superposed cells, the lower triangular,
suffused with blackish at the base; the two upper much flattened,
their septa horizontal; terminal cell small; an inconspicuous trun-
cate hyaline projection arising near the trichogyne. Spores 28-
30 X 3 ft. Perithecia 100 X 35-40 /i. Basal cells 40-50 p. Total
length to tip of perithecium 150 p..

On Haliplus ruficollis and Cnemiolottis muticus, Connecticut.

Occurs rarely on the right elytron of its host, usually upon Hali-
pbus, a single specimen only having been found on Cnemidotus.
It is distinguished from all other species by the three superposed
basal cells of the receptacle, the upper of which appears to be what
is usually the middle of the three cells which normally form the
base of the perithecium. The inflated, abruptly papillate perithe-
cium is also a distinguishing character.

Heimatomyces lichanophorus, nov. sp.

Hyaline except for the suffused basal cell. Perithecia bent out-
wards at an angle from the basal part of the receptacle, tapering
slightly to the papillate apex. Basal cell of receptacle enlarged
and greatly elongated, more or less intensely blackened above its

OF ARTS AND SCIENCES. 33

hyaline base; sub-basal cell flat and almost obsolete. Terminal
and subterminal cells together forming a straight finger-like pro-
jection as long as or longer than the perithecium. Spores 33-37
X 2.5-3 ix. Perithecia 65-90 X 30 fx. Total length to tip of peri-
thecium 150-180 fi. Basal cell 90-110 fx.

On Laccophilus maculosus, Connecticut.

This species is confined to the median inferior anal plate of ks
host, and has only been observed upon males. It is not to be con-
fused with any other species, being distinguished by its elongated
basal and apical cells, almost black and white color, and papillate
divergent perithecium.

Heimatomyces rhynchostoma, nov. sp.

Evenly suffused with yellowish brown. Perithecia relatively
large, abruptly hooked at the broad apex, so that the papillate tip
is turned inwards and is lateral in position. Basal cell of recepta-
cle comparatively short, slightly inflated: sub-basal cell flattened:
terminal and subterminal cells forming an outwardly curved, finger-
like appendage exceeding the perithecium; the subterminal cell
continued into a short well marked hook. Spores 26 X 3 fx. Peri-
thecia 75 X 22 fx. Total length to tip of perithecium 100 fx. Basal
cells of receptacle 25-30 fx.

On Laccophilus maculosus and Hydroporus spurius, Connecticut.

Occurs rather rarely on the margin of the right elytron, from
the surface of which the perithecium projects in a characteristic
fashion. The broad hooked apex of the perithecium and the finger-
like development of its distal portion distinguish this species from
any other form.

Heimatomyces uncistatus, nov. sp.

Evenly suffused with pale yellowish brown. Perithecia large,
curving evenly inwards to the somewhat pointed apex. Basal cells
of the receptacle rather slender, the terminal cell pushed to one
side and bent past the apex of the perithecium by a somewhat
indurated, blunt, hooked outgrowth from the subterminal cell.
Perithecia 75-85 X 20 fx. Total length 110-130 fx. Basal cells
of receptacle 37 fx.

On Laccophilus macuiosus and Hydroporus spurius, Connecticut.

A rather rare species, occurring in groups on the inferior surface
of the abdomen of its host, and distinguished by the peculiar
development of the subterminal cell of the receptacle.

VOL. XXVII. (n. 8. xix.) 3

34 PROCEEDINGS OF THE AMERICAN ACADEMY

Heimatomyces marginatum, nov. sp.

Long and slender, at first nearly hyaline, then yellowish. Peri-
thecia straight, then suddenly bent inward below the hyaline,
neck-like, strongly curved tip. Basal cells of the receptacle sub-
triangular, the sub-basal half as large as the basal, the three cells
at the base of the perithecium more than usually developed : the
terminal cells all becoming black and opaque at maturity; the ter-
minal one continued by a squarish outgrowth basally hyaline, at
first lateral and external, becoming terminal (the true apex of the
cell being pushed inwards and becoming lateral), hardly exceeding
the tip of the perithecium which it conceals. Spores 30 X 3/i.
Perithecia 95-110 x 22 jx. Total length to tip of perithecium
140-160 jx. Basal cells of receptacle 25 li.

On Laccophilus maculosus and Hydroporus spurius, Connecticut,
Maine.

A form peculiar for the modification of the terminal cells of the
receptacle, which makes the perithecium appear as if bordered by
a black band. It is found in company with H. paradoxus, and
recalls the supposed genus Chitonomyces, which is said to be simi-
larly associated on the left elytron of its host.

CERATOMYCES, nov. gen.

Receptacle reduced, consisting of a small number of basal cells,
above which it is directly continued by the basal cells of the peri-
thecium and antheridial appendage. Perithecia highly developed,
the walls composed of four longitudinal rows of superposed cells,
the outer row continued into a horn-like appendage. Antheridial
appendage arising at the base of the perithecium, composed of
a series of superposed cells the upper angles of which may be
cut off to form the base of filamentous appendages (antheridia ?).
Asci subclavate, 4-spored. Spores fusiform or acicular, once sep-
tate, involved in mucus.

Ceratomyces mirabilis, nov. sp.

More or less deeply suffused with yellowish brown. Perithe-
cium elongate, the walls composed of longitudinal rows of super-
posed cells, about twenty-three in each row, the cells of adjacent
rows alternating, their long axes transverse : the outer row con-
tinued below the apex of the perithecium as a curved horn-like
projection, basally constricted and suffused, tapering distally to a

OP ARTS AND SCIENCES. 35

rounded tip (in unbroken specimens), and made up of a series
(ten to sixteen) of more or less cylindrical superposed cells. Tip
of perithecium subhyaline, subacute, curved towards the perithe-
cia] appendage. Antheridial appendage arising from the receptacle
slightly above the ascogenoxis cell of the perithecium ; subconical,
composed of a variable number of superposed cells, from the upper
angles of which may be cut off, by an oblique partition, small
cells which give rise to the antheridial branches, the latter slen-
der, hyaline, septate, simple or branching, evanescent. Receptacle
composed of three superposed cells, deeply blackened except along
the outer edge, surmounted by a larger inner blackened cell and two
smaller outer subhyaline cells; the basal cell partly subhyaline,
the foot large and wedge-shaped, the axis of the receptacle strongly
bent between the basal and sub-basal cells. Spores slender, one
or more times spuriously septate, fusiform or slightly rounded at
the apex, 100-120 X 4 ti. Asci flattened, subclavate on a short
curved pedicel. Perithecia 280-295 X 65-75 //,. Antheridial ap-
pendage one half to two thirds as long as the perithecium. Peri-
thecial appendage 180-200 ti. Total length to tip of perithecium
(maximum) 450 /x. Receptacle 150 X 75 /x.

On Trojristernus glaber and T. nimbatus, Connecticut.

Taken in a single locality, at Milford. The trichogyne arises
apparently from the angle between the perithecium and the anthe-
ridial appendage, thus indicating a probable relationship to the
Heimatomyces section of the family. The parasite inhabits the
inferior surface of its host in various positions.

Ceratomyces camptosporus, nov. sp.

Closely resembling the last in general appearance. Perithecia
strongly curved near the base, proportionately stouter and shorter,
each row of cells made up of from thirty-five to forty members,
which, especially in the external row, are successively inflated,
giving the outline on this side a stronglr corrugated appearance:
perithecial appendage of fewer, longer cells, not bent or blackened
towards its base. Receptacle very small, triangular, straight, of
not more than two or three superposed cells, the lower quite opaque.
Antheridial appendage arising from a short curved basal cell, above
which it is abruptly inflated, tapering thence to a rather slender
apex. Spores more slender than in C. mirabilis, tapering at both
extremities, slightly swollen and strongly bent near the base, 110
X 3.5 /x. Perithecia 275 X 85-90 jx. Receptacle 90 X 50 ll.

36 PROCEEDINGS OF THE AMERICAN ACADEMY

On Tropisternus glaber, Connecticut.

This species occurs with the last, but more rarely, and was at
first mistaken for a mere variety of it. The differences, however,
are important and constant, the peculiarity of structure presented
by the spores being unique in the group.

CORETHROMYCES, nov. gen.

Receptacle reduced to a basal with two or three terminal cells,
giving rise on one side to the free perithecium, on the other to
several long straight rigid cylindrical jointed appendages, which
bear externally at short intervals numerous secondary appendages.

CORETHROMYCES CrYPTOBII, nOV. Sp.

Perithecium (immature) long and narrow, the tip bent slightly
inwards. Primary appendages three or four in number, brownish,
rather closely 11-12 -septate, cylindrical, straight, tapering slightly;
the secondary branches simple, aseptate or pseudoseptate, some-
what divergent, comprising a row of larger brown appendages on
either side, between which arise a few smaller hyaline ones; the
larger appendages about equal in number to the segments of the
primary appendage (six to seven). Receptacle opaque above the
small hyaline basal cell. Primary appendages 150-160 X 8-10^.;
secondary appendages (longer) 100-110 X 5.6 /*,. Receptacle 75 X
40 jx. Perithecium (immature) 100-110 X 20 fx.

On Cryptobium pallipes, Virginia (Pergande).

A single immature specimen of this remarkable genus was found
growing on one of the posterior legs of its host. The highly differ-
entiated appendages are quite different in character from those of
any other genus. In their natural position they almost wholly
obscure the perithecium, and, springing from the greatly reduced
receptacle, present the appearance of a brush-like tuft, the true
nature of which is not at once apparent.

ACANTHOMYCES, nov. gen.

Perithecia as in Laboulbenia, clearly differentiated from the re-
ceptacle. Main axis of the receptacle composed of superposed
squarish cells, and, above its basal cell on the inner side, of a
series of smaller appendage-bearing cells extending up to and
around the base of the perithecium : the appendages simple, rigid,
septate. Spores as in Laboulbenia.

OF ARTS AND SCIENCES. 37

AcANTHOMYCES LASIOPHORA, I10V. sp.

More or less suffused with blackish brown. Perithecia borne on
the apex of the receptacle, somewhat inflated, nearly symmetrical,
tapering to a rather blunt apex. Appendages arranged in two
rows of larger bristle-like members, hyaline at the tips, blackish
below, running from the apex of the basal cell (one opposite each
upper inner angle of the cells of the main axis) to the apex of the
receptacle, where they envelop the base of the perithecium : from
the cells of the receptacle between these two rows arise smaller
appendages, which become more numerous towards its extremity.
Receptacle slender at the base, expanding upwards, consisting of a
main axis of about twelve superposed vertebra-like cells, at first
hyaline, becoming blackish, and of a series of smaller cells al-
most completely concealed by the appendages. Spores involved in
mucus, 1-septate, 30 X 3 /a. Perithecia 140-145 X 50 fx. Larger
appendages 75-90 fx. Receptacle 175 //,.

On Atranus pubescens, Connecticut.

The slightly branched terminal trichogyne of this singular form
is hidden between the appendages at maturity. The character of
the antheridia could not be determined from the material exam-
ined, and the minute structure of the receptacle, apart from the
main axis, is almost completely hidden by the appendages.

Laboulbenia compacta, nov. sp.

More or less tinged with olive-brown. Perithecia moderate,
tapering towards the somewhat coarse-lipped, outwardly oblique
apex. Pseudoparaphyses forming a dense tuft, hardly exceeding
the perithecia in length, simple, or once branched above the basal
cell, tapering evenly to the apex, 1-3-septate, tinged with brownish
near the base: arising from a broad cellular base of eight or more
cells, above a more or less well marked disk of insertion situated
just above the base of the perithecium. Receptacle very short and
stout, subtriangular : cell II. much broader than its length, wedge-
shaped distally : cell III. greatly reduced, broad and fiat : cell V.
unusually large, its base resting on cell III. Spores 60 X 4 /x.
Perithecia 110 X 40 /x. Pseudoparaphyses 90-100 jx. Total length
to tip of perithecia 180-190 /x. Greatest breadth 65 fx.

On Bembidium sp., Maine.

A small well marked species of the luxurians type, differing in
its peculiar shape and abundant straight appendages inserted on a

33 PROCEEDINGS OP THE AMERICAN ACADEMY

multicellular base, which is more highly developed than in L. lux-
urians or L. fumosa.

Laboulbenia luxurians, Petr.

A form which appears to be identical with this species, and
closely allied to L. fumalls, occurs usually on the tips of the
elytra of species of Bembidium in Maine, and has also been sent
to me from Washington by Miss Parker.

Laboulbenia variabilis, nov. sp.

At first hyaline, becoming more or less tinged with brown.
Perithecia moderate, tapering only slightly to the rather blunt,
outwardly oblique, coarse-lipped apex, which is more or less deeply
blackened below, especially on the inner side. Pseudoparaphyses
very variable in number, sometimes hardly branched, sometimes
forming a dense fascicle : arising more or less indefinitely from a
small number of basal cells above cells IV. and V. of the recepta-
cle, from which they are not separated by any disk of insertion :
the basal portion short, constricted at the blackish septa, the seg-
ments slightly inflated; the distal portion slender, cylindrical,
aseptate or obscurely septate, hardly tapering; often hardly ex-
ceeding the perithecium, sometimes several times its length.
Antheridia overlapping one another on special lateral branches,
forming a subcorneal cluster. The plane of insertion of the
pseudoparaphyses usually opposite the middle of the perithecium,
sometimes carried beyond its apex by the elongation of cells III.
and IV. of the receptacle. Receptacle medium or much elongated;
cell V. often enlarged, and protruded along the inner face of the
perithecium, so as to throw the pseudoparaphyses and their inser-
tion outwards. Spores 50-60 x 6 ll. Perithecia 92-130 x 33-50 /*.
Pseudoparaphyses 150-480 p. Total length to tip of perithecium
180-550 fi.

On Omophron Americanum, Chlcenius Pennsylv >anicus, Connecti-
cut. On Nebria pallipes, Chlcenius cestivus, Virginia (Pergande).
On Platynus extensicollis, Patrobus longicornis, Pterostichus cor-
vlnus, S. Dakota (Aldrich).

A species remarkable for its great variation in size even on the
same host, as well as the irregularities connected with the number
and relative insertion of its pseudoparaphyses. The latter are
peculiar from their differentiation into a basal short portion, com-
posed of a small number of slightly inflated cells, and a distal

OP ARTS AND SCIENCES. 39

filamentous, scarcely septate portion. The subcorneal clusters of
antheridia are also quite peculiar to this species, and distinguish
it from other known forms.

Laboulbexia Galerit^e, nov. sp.

Perithecia punctate becoming almost opaque, elongate, subcylin-
drical, slightly rounding to the base and rather abruptly tapering
to the blunt apex: the latter slightly oblique outwards. Pseudo-
paraphyses simple, septate, slightly constricted at the lower septa
and tapering towards the somewhat blunt apex: arising from a
subcorneal, cellular base in (usually three) nearly vertical rows,
from three to four pseudoparaphyses in each row: the base of in-
sertion hyaline above, nearly black below, placed below the base
of the perithecium. Receptacle moderate, or slightly elongate;
cells III., IV., and V. externally, or almost wholly, opaque.
The basal cells of the perithecium greatly enlarged and elongated,
so as to form a distinct, stout, neck-like hyaline base, on which
it is borne entirely free. Spores 50 X 5.5 /z. Perithecia 155 X
37 fx. Pseudoparaphyses (long) 350 p. Total length to tip of
perithecia 375 p.

On Galerita janus, T>. C. (Pergande).

This very distinct and peculiar species occurs, often in great
numbers, on all parts of its host, and is distinguished by the in-
sertion of it's paraphyses on a subcorneal cellular base, as well as
by the neck-like base of its perithecium.

Laboulbenia Gyrinidarum, nov. sp.

Blackish brown, nearly or quite opaque. Perithecia large, sub-
conical or subcylindrical : usually straight external^, rounded
internally ; the apical lobes modified to more or less distinct, short,
straight, simple appendages. Pseudoparaphyses hyaline or basally
brownish, arising in a broad dense tuft from several basal cells,
several times irregularly branched, rather closely septate basally
and constricted at the septa, distally sparingly septate, slender,
cylindrical; seldom extending more than two thirds of the dis-
tance from the base to the apex of the perithecium. Receptacle
distally very broad, cells I. and II. short and slender, rarely
elongate. Asci 4-spored, 150 X 37 X 18 p. Spores 90 X 7-8 p.
Perithecia 190 X 90 p. Pseudoparaphyses 100-110 p. Total length
to tip of perithecium 480 p: greatest breadth 160 p.

On Gyrinus sp., Connecticut.

40 PROCEEDINGS OF THE AMERICAN ACADEMY

This constitutes the second species of the genus which is pecu-
liar to an aquatic host; but is quite distinct from the form rep-
resented by the excellent figures of Eobin under the name of
L. Guerinii. Its paraphyses recall those of L. variabilis in their
general structure; but in no other species are they so densely
tufted, while the appendiculate apex of the perithecium is unique
in the genus. The species is a common one, growing upon the
elytra as a rule, and was collected in numerous localities about
New Haven.

Laboulbenia Brachini, nov. sp.

More or less evenly suffused with amber-brown. Perithecia
rather short and stout, tapering to the broad, often abruptly trun-
cate, black apex, the lip edges of which are hyaline. Pseudo-
paraphyses hardly exceeding the mature perithecium, arising
primarily from two basal cells, — a larger inner nearly hyaline,
a smaller outer more or less opaque, — on which are closely set, so
as to form almost a semicircle, the ten or more basal cells of the
simple, slightly curved (outward) and tapering pseudoparaphyses,
the inner hyaline, the outer blackened at the base. Disk of inser-
tion oblique, in position between the lower thirds of the perithe-
cium. Receptacle normal, short or sometimes elongate. Perithecia
125-185 X 75 fi. Pseudoparaphyses (long) 150 p. Total length to
tip of perithecium 550 fx (average 375 p) : greatest breadth 110 /x.

On Brachinus sp., Virginia (Pergande).

A species readily distinguished from L. Rougetii, which occurs
in Europe on a similar host, by its fan-like pseudoparaphyses, am-
ber color, and black-tipped perithecium. The specimens bearing
the parasite, usually at the base of the elytra, were taken by Mr.
Pergande in dry situations near Washington, D. C.

Laboulbenia curtipes, nov. sp.

Olive-brown except for the hyaline contrasting basal cell of the
receptacle. Perithecium large, containing very numerous asci
and spores, inflated externally, nearly straight, the rather small
apex strongly bent outwards. Pseudoparaphyses arising from two
blackened basal cells, in a small tuft, slender, tapering, straight,
inconspicuous, hardly exceeding the middle of the perithecium.
Receptacle small and short in proportion to the perithecium ;
cell I. hyaline, contrasting with cell II., which is short, broad,
and distally wedge-shaped. Spores 40 X 4 /*. Perithecia 110-135

OP ARTS AND SCIENCES. 41

X 55 p. Pseudoparaphyses 55 p. Total length to tip of perithe-
ciuin 200-225 p : greatest breadth 50-55 p.

On Bembidium bimaculatum, Washington (Miss Parker).

This species occurs usually upon the posterior legs of its host,
and is peculiar for the great number of spores which it produces in
its unusually large inflated perithecia, the pseudoparaphyses being
almost obsolete in mature specimens.

Laboulbenia parvula, nov. sp.

More or less suffused with dark olive-brown. Perithecia slightly
inflated, darker at the base and apex, the latter expanded slightly,
rather large, the coarse lips oblique inwardly or nearly horizontal.
Pseudoparaphyses exceeding the tip of the perithecium, arising
primarily from two basal cells, above which from six to eight ulti-
mate branches are formed, the outer larger, straight, divergent,
nearly opaque at its base ; the rest straight, nearly hyaline : disk
of insertion black, just above the base of the perithecium in posi-
tion, and producing a constriction at the apex of the receptacle.
Receptacle short, cells III.-VII. becoming nearly opaque, cell II.
less deeply colored, cell I. nearly hyaline, or suffused only on the
outer side. Spores 35-40 X 4 p. Perithecia 100 X 40 p. Total
length to tip of perithecium 165-180 p : greatest width 44-50 p.

On Platynus extensicollis, Virginia (Pergande). On Bembidium
bimacidatum, Washington (Miss Parker).

A small species, without striking peculiarities, yet easily sepa-
rated from any form known to me, and apparently constant in its
characters, as shown by a comparison of material from two such
widely separated localities as those above mentioned.

Laboulbenia inflata, nov. sp.

Hyaline or slightly tinged with brownish. Perithecia rather
small, straight, the tip bent outwards, a black patch below the
rather coarse hyaline lips. Pseudoparaphyses two to four in num-
ber, peculiar from the inflation of the first two or three basal cells,
above which they are rigid, thick-walled, curved slightly outwards,
hyaline, tapering to a blunt apex; the basal cell of the outer
pseudoparaphysis is much larger than the rest, short, flat, and
much inflated. Receptacle normal, the cell walls unusually thick.
Pseudoparaphyses 120 p. Perithecia 85 X 30 p. Total length to
tip of perithecium 190 p.

On Bembidium sp., S. Dakota (Aldrich).

42 PROCEEDINGS OP THE AMERICAN ACADEMY

The short inflated basal cells of the rigid, nearly hyaline para-
physes, associated with a definite disk of insertion, distinguish
this small species from other forms with which it might possibly
be confused. Three specimens only, in good condition, were found
growing on the elytra of the host.

Laboulbenia recta, nov. sp.

Olivaceous. Perithecia rather small, slightly rounded to the
large, almost cylindrical, abruptly truncate, blackened apex, the
lips of which may be very slightly oblique inwards. Pseudopara-
physes stout, arising from two basal cells, the outer twice as long
as the inner, each giving rise to from two to three branches, which
may in turn be once or twice branched, all the branches parallel
to one another and to the main axis of the receptacle and of the
perithecium, which they exceed by more than half its length: disk
of insertion thick, black, horizontal, placed opposite the middle
of the perithecium. Receptacle normal, rather elongate. Spores
75-80 X 6-7 n. Pseudoparaphyses 175 p. Perithecia 150-180 X
50-75 ix. Total length to tip of perithecium 380 /x : greatest breadth
75-110 M.

On Platynus extensicolUs, Connecticut.

A rare species, occurring on the legs of its host in company with
L. scelopkila, to which it bears some resemblance in the branching
of its paraphyses. A small number of specimens from three locali-
ties near New Haven show little variation.

Laboulbenia contorta, nov. sp.

More or less suffused with reddish brown. Perithecia suffused
with blackish brown, sometimes nearly opaque, considerably in-
flated, strongly curved outwardly at the apex, so that the nearly hya-
line, very broad, hatchet-shaped lips are almost vertical in position :
the whole perithecium at maturity usually so twisted near the base
that its axis crosses the pseudoparaphyses obliquely. Pseudopara-
physes exceeding the perithecium by about twice its length, aris-
ing from two basal cells, the outer twice as large as the inner; the
outer pseudoparaphysis simple or once branched above the sub-
basal cell, the inner sometimes branched above the basal and sub-
basal cells : disk of insertion thick, black, placed about one third of
the distance from the base to the apex of the perithecium. Recep-
tacle abruptly expanded above cell II., cells I. and II. rather
elongate, the rest somewhat reduced and rounded. Spores 75 X 5 /a.

OF ARTS AND SCIENCES. 43

Perithecia 150-180 X CO-75 it. Total length to tip of perithecium
330-400 it: greatest width 90-100 it. Pseudoparaphyses 300 ti.

On Platynus extenslcollis, Connecticut.

This peculiar species occurs rarely on the inferior lateral face of
the thorax of its host, seldom elsewhere, and is ahundantly distinct
from any other species of the flagellata type. The twisting of the
perithecium is apparent only in mature specimens, yet this ruodifi-
cation seems characteristic and analogous to the more pronounced
distortion of the following species.

Laboulbenia gibberosa, nov, sp.

More or less faintly tinged with reddish brown. Perithecia
short, stout, expanding slightly from the base to a conspicuous
external hunch just below its broad, almost truncate apex. Pseudo-
paraphyses arising from a large outer and a very small inner basal
cell, simple or bearing two to three branches always above the sub-
basal cell, constricted at the septa, the segments becoming slightly
inflated, the tips usually curved and tapering: the disk of inser-
tion small and thick. Receptacle elongate, strongly twisted above
cell II., the twist continued by cells IV. and V., which are much
elongated, and carry the pseudoparaphyses out at right angles to
the axis of the perithecium. Spores 50 X 4.5 it. Pseudoparaphyses
180 it. Perithecia 125 X 50 it. Total length to tip of perithecium
500-550 M.

On Platynus extenslcollis, Connecticut.

A number of specimens of this rare and singular species show
that the twisted receptacle is a constant character, which is some-
times carried to such an extreme that the ordinary direction of
the pseudoparaphyses is reversed, the elongation and curvature of
cells IV. and V. bending them towards the base of the receptacle.
The species is large and unusually elongate, growing on the infe-
rior surface of its host, usually near the base of the middle pair

of legs.

Laboulbenta Schizogenii, nov. sp.

Hyaline or pale yellowish. Perithecia rather short, smoky or
nearly opaque, especially towards the apex, the prominent rounded
hyaline lips of which are slightly oblique outwards. Pseudo-
paraphyses from two basal cells, each giving rise to two to four
branches, which may in turn be one to three times branched : the
branches all hyaline or pale yellowish, slightly curved and rounded
at their extremities: disk of insertion small and thick, very ob-

44 PROCEEDINGS OF THE AMERICAN ACADEMY

lique, placed above the middle third of the peritheciurn, from which
it is wholly separated through the elongation of cell V. Recep-
tacle usually elongate, cell V. being continued beyond the inser-
tion of the pseudoparaphyses nearly to the lips of the peritheciurn,
cells IV. and V. being thus almost superposed. Spores 70 X 5.5 /*.
Perithecia 100-120 X 50-55 p. Pseudoparaphyses (long) 270 fi.
Total length to tip of peritheciurn 350-375 p : greatest width 75 ft.

On Schizogenius lineolatus and S. ferruglneus, Connecticut.

A rare species, at once separable by the peculiar relative position
of the pseudoparaphyses, and the unusual elongation of cell V.,
which is sometimes approached by specimens of L. variabilis.

Laboulbenia pedicellata, nov. sp.

Hyaline, becoming brownish, long and slender. Perithecia dis-
tally subconical, inflated on the inner side, the apex rather broad
and usually somewhat pointed, nearly symmetrical. Pseudopara-
physes, when perfect, exceeding the peritheciurn, arising primarily
from two basal cells, the outer twice as long as the inner, bearing
at its apex a roundish cell, from which arise three branches two to
three times subdichotomously branched, the branches curved and
more or less hooked at the apex. After fertilization, the inner
basal cell produces a number of branches curved towards the peri-
theciurn, and often producing secondary branches : disk of inser-
tion rather broad, blackish, oblique, inserted just above the base
of the peritheciurn. Receptacle long and slender through the great
elongation of cell II. Spores 50 X 3.5 /i. Perithecia 90-95 X
36-40/1. Pseudoparaphyses 90-100 fi : longest 150 /x. Total length
to tip of peritheciurn 300 /z : greatest width 45 fi.

On Bembidium sp., Maine.

Allied to L. vulgaris, from which it is distinguished by its slen-
der, elongate, cylindrical basal cells, and by its inflated, pointed
peritheciurn, which is also differently situated in relation to the
insertion of the pseudoparaphyses.

Laboulbenia vulgaris, Peyr.

A form referable to this sjiecies, and occurring on the elytra of
species of Bembidium, has been received from Washington on hosts
collected by Miss Parker, and is also not uncommon on Bembidia
taken in Maine. The figures and description given by Peyritsch
leave much to be desired, yet the determination seems tolerably
certain.

OF ARTS AND SCIENCES. 45

Laboulbenia NEBRiiE, Peyr.

This well marked form can hardly be confused with any other
described species, and is very common on Nebria pallipes in Con-
necticut, covering all parts of the host with a furry mass of indi-
viduals. It was accidentally omitted from my previous note, though
incidentally referred to.

Laboulbenia truncata, Thaxter.

Additional material of this species shows that in perfect and
mature specimens the inner pseudoparaphysis develops a long
branch, which extends nearly at right angles to the axis of the
perithecium, and to a considerable distance beyond it, thus pre-
senting a very characteristic appearance. The species has been
received on various species of Bembidium from Virginia (Pergande)
and Washington (Miss Parker).

46 PROCEEDINGS OP THE AMERICAN ACADEMY

V.

ON A THEOKEM OF SYLVESTER'S RELATING TO
NON-DEGENERATE * MATRICES.

By Henry Taber, Clark University.

Presented March 9, 1892.

In" his Memoir on Matrices, Cayley enunciated the theorem
that the most general matrix commutative with a given matrix was
a rational integral function of it. Of this theorem Sylvester gave
a proof, in the Johns Hopkins University Circulars, Vol. III.
pp. 34 and 57, for the case in which the latent roots of the given
matrix were all distinct, hut pointed out that, when the latent
roots of the given matrix were not all distinct, the theorem did not
always hold. Subsequently, in the Comptes Rendus, Vol. XCVIII.
p. 471, Sylvester stated that he had proved that Cayley's theorem
held for a matrix of the third order which was not degenerate (de-
ror/atoire),^ irrespective of equalities between its latent roots; and
he further stated that Cayley's theorem was probably true for non-
degenerate matrices of any order; i. e. that the most general ma-
trix commutative with a non-degenerate matrix of any order
whatever was a rational integral function of it. I shall in this
paper verify this conjecture of Sylvester's. The theorem follows
very simply from one given by the author in a note in these Pro-
ceedings for May 26, 1891,$ which contains the complete solution
of the problem to find the most general matrix commutative with
a given matrix.

The theorem is then to be proved for the case in which the latent
roots of the given matrix are not all distinct. If the distinct la-
tent roots of the given matrix Q are gx, g2, g3, etc., of multiplicity

* Sylvester employs the term matrice derogatoire (Comptes Rendus, Vol.
XCVIII. p. 471) to denote a matrix whose identical equation is of order lower
than the order of the matrix ; such a matrix I term a degenerate matrix.

t See preceding note.

t These Proceedings, Vol. XXVI p 64.

OF ARTS AND SCIENCES.

47

m, n, p, etc., respectively, then Q may be written asuflw \ where
to is a non-vacuous matrix, and

e = r

h

0.,

Os

0,

in which all the constituents are zero except those in the squares
#i> 02> @39 etc-> along the principal diagonal; these correspond re-
spectively to the latent roots gu g*, g3, etc., and are subsidiary
matrices each of order equal to the multiplicity of the respective
latent root to which it corresponds. Since O is supposed non-de-
generate, the characteristics of its latent roots are (m; 1, 1, ... . 1),

(n; 1,1, 1), (p; 1,1, 1), etc., respectively. Moreover,

since the characteristics of g1 are (m; 1, 1, .... 1),

in

h =

gi 1 0 0 0 . . .

0 fi! 1 0 0 ... .

0 0 5/1 1 0 . . .

0 0 0 ft 1 ... .

0 0 0 0^.. .

► ;k

In like manner, in the subsidiary matrix 62 the principal diag-
onal is bordered on the right by unity, and the constituents in the
principal diagonal are all equal to g2, the remaining m2 — 2 m + 1
constituents being zero; similarly with respect to the remaining
squares, 63, etc.

Let &u #2, etc., denote the matrices obtained from 6 by erasing
successively all the constituents of 6 except, first, those in the
square 61; second, those in the square 02, etc. Then

0 = #! + #2 + #3 +

48 PROCEEDINGS OF THE AMERICAN ACADEMY

and since the #'s are nilfactorial together, i. e. since &i &2 — #2 l^i
= 0, etc., therefore

etc., etc.

Consequently, if f{&) is any rational integral function of 6 of
which k is the term independent of 6, and if f{&) = f {&) — k,
then

f(0) =f(6) + k =/(*0 + f(&2) + /(*,) + •••• + 7c.

Let [r, s] denote the matrix whose constituents are all zero
except that in the r-th row and s-th column, which is unity. We
have then

*i = 9x timr [?, r] + ^V [r, r + 1],

#2 = ff2 2i" [m + r, m + r] + S/^1 [m + r, m + r + 1],

#3 = #3 Sir [m+w+r, m+n+r] + 2/7 * [wi + w + r, m + rc+r+1],
etc., etc.

By the laws of multiplication of the symhols [r, s], viz.
[r, s] [*, f] = [r, t], [r, s] [*, v] = 0 (5 =t *)>

it follows that

xV - r/i2 XTr [*. '] + 2 * SiV1 [r, r + 1] + SiT1 [r, r + 2],

#i3 - ?i3 S™ [r, r] + 3 fl« S/V1 [r, r + 1] + 3 ffl S.V" [r, r + 2]

+ Srr3 [r, r + 3],

xV = ^S * [r, r]+^*" XT' ['1 •+1]+2^^""f[^ y+2]

1 dm_1

+ •••• + (^^iyt^-^[l,m].

Therefore, if f'(ff), /"(#)> e^c., denote respectively the first,
second, etc., differential coefficients of f(g) with respect to g,
then

OP ARTS AND SCIENCES. 49

/(».) = /(?.) s;;[»', .-]+/'&.) 2 *"' [r, rf i]+-^ s,"r! [<•, '-+3]

Similarly, we have
/(#„) = /(^2) 2i? [m + r, m + r~\ + f fa) t* [m + r, m + r + 1]

+ ^^^n72[m + r, m + H-2] + . . . . +^^[m+l3 » + „]

== SoT1 {^r^ SiV [* + r, m + r + j] J- ,

/(#8) =/(gr8) &' [m + n + r, m + ft + r]

+ /' (fj3) %p7l [m + n + r,m + n + r + 1]

+ (1&L %*-*\m + 7i + r, m + n + r+2] + ---

+ J7 ^ \m + n + l,m + n+p\

0-l)!L

= SoP71|^^SiVs[m + « + r, m + n + r + s^,
etc., etc.
And since /'((/) =f{g), f"(g) =f"(ff), etc., and

1 = 27™ [r, rJ + Si" [w + r,m+ r]

+ Si'[m + » + )*, m + ^ + r] H ,

it follows that
/(*)=/(«) + *

+ SoT1 j^r^Xi"[w + r, m + r + s~\\

+ 20Pji i /"(?») ^ [m + n + r> m + n + r + s]\+ etc.

VOL. XXVII. (n. S. XIX.) 4

50 PROCEEDINGS OP THE AMERICAN ACADEMY

Let now

/i(0) = [(<? - ft)- - (ft - ft)m]» [(fl - ft)- - (ft - sOmp . . . . ,

the remaining factors corresponding to the remaining latent roots;
then for g = ft ,

fx(9) = /ifa) =t 0, f^ff) = 0, f{\g) =0, .... f^~\g) = 0;

for g = ft, fx (g) = 0, and likewise its first n — 1 differential
coefficients ; similarly, for g = ft, fx (g) and its first p — 1 differ-
ential coefficients are all zero, etc. Therefore

/i(0) _ v m r 1
/i(^)_^lrLr'rJ'

It may be shown in like manner that

A (9x)

(6 - ft) = &-r"» [r, r + I],

£|I(0_ft)2 = SlV[r,r + 2],

^(^-ftr-^ci, H.

Similarly, if

then it may be shown in like manner that
4|®. = S£ [» + r, m + r],

4^r(tf-^ = &";1[i»+r,»+r+l]l

/ 2 Gfe)

4t^ C^-^)"-1 - [» + 1, m + ft],

72 (.#2,)

etc., etc.

OF ARTS AND SCIENCES.

51

Now, by reference to the theorem referred to above, it will be
seen that if <£ is the most general matrix commutative with £2,
then <f> may be written as w^w-1 where

= c

1)1

V2

V3

D.

in which all the constituents are zero except those in the squares
Vi> Vv etc, along the principal diagonal, and these square arrays or
subsidiary matrices are of order equal respectively to the order of
the subsidiary matrices 0V 62, etc., to which they severally corre-
spond; moreover,

Vi -

m

«i h

ci

*1

«1 •

. .

0 ax

h

C]

dx ■

0 0

«i

h

ci •

0 0

0

«i

h •

. •

0 0

0

0

at .

• •

fin

V2

0.-2 h

c2

d.

e.2 ....

0 a2

h

c2

d.2

0 0

a2

&2

Co ....

0 0

0

°2

b, ....

0 0

0

0

a2 ....

etc. . .

In

etc., etc.

52 PROCEEDINGS OP THE AMERICAN ACADEMY

Therefore, if el5 e2j etc, severally denote the matrices formed from
7] by erasing successively all its constituents except, first, those in
the square rji, second, those in the square -q2, etc., then

V — ci + c2 + >

and

4 = «i2i? [r, r] + ftiSiV1 [r, r-+ 1] + c^i"*"2 [r, r + 2]

+ 4AV [r, r + 3] + ei 2iV4 [r, r + 4] + • • • •

€2 = a2Si" O + r, m + r] + JjSw1 [m + r, m + r + 1]

+ c2 ^i"72 [«» + r, m + r + 2] + d2 Si" 73 [m + r, m-+ r + 3]
+ e2 Si"74 [m + r, m + r + 4] + • ■ • ■ ,
etc., etc.

But by what has just been proved it follows that
/i \9v

e2 = ^M-{a2 + b2(o-rj2) + c2(e-g2y+d,(e-92y+e2(o-gi)i+.. . .},

/ 2 \9v

etc. Consequently 77 is a rational integral function of 6. Let
rj=f(0), where f{6) denotes the most general rational integral
function of 6 ; then, since

w./(0). or1 = /<Q),

the most general matrix commutative with fi is

cf> = urjw-1 = w. f{6) . ca-1 = /(fi).

Worcester, Mass., January 2, 1892.

OP ARTS AND SCIENCES. 53

POSTSCRIPT.

Worcester, Mass., March 26, 1892.

I find that the solution of the matrical equation fi<£ = <£fi given
in a note in these Proceedings, May 26, 1891, and upon which
the proof of the theorem given above is based, gives the complete
solution of the more general matrical equation O c/> = (f> O' for that
case in which it may be assumed that the determinant of <f> is not
null. For this case the latent roots of ft' are identical with those
of ft, and have, respectively, the same characteristics, i. e. the nulli-
ties of successive powers of ft' less any latent root g are respectively
equal to the nullities of successive powers of ft — g. Therefore,
if the canonical form of ft is to 0 uT1, the canonical form of ft' is
w 0 a/-1.* Matrices thus related are termed by Weyr matrices of
the same kind.

If, then, in the equation

ft <f> = cf) ft ,
ft and ft' are replaced by their equivalents, it becomes

CO 6 (o—1 <f> = <}> to' 6 co'— 1,

that is,

6 . w>~ ! c/> <o' = co— * cf> to' . 0.

If, now, we put

the equation becomes

\tf = CO (fi CO ,

6 if, = if/ 6.

But the most general solution of this equation is given in the note
above referred to; the most general matrix commutative with 6 is
there denoted by -q. Therefore, the most general solution of the
matrical equation

<£ ft = ft' <£
is

c£ = co if/ to'- ,

* For explanation of the term canonical form of a matrix, see paper referred
to, these Proceedings, Vol. XXVI p. 64.

54 PROCEEDINGS OF THE AMERICAN ACADEMY

if the canonical forms of O and Cl1 are respectively w 6 w-1 and
g/0w'-1, and provided \p is the most general matrix commutative
with 6.

This solution of the equation Cl <j> = <£ Cl', as also the ahove
mentioned solution of the equation O </> = c/> O, depends upon the
reduction of a matrix to its canonical form. In the assumed
canonical form of Cl, viz. co 6 to-1, the matrix 6 is dependent solely
upon the characteristics of the latent roots of Cl. Having deter-
mined the latent roots of Cl and their characteristics, if one value
of co is known, the solution of the preceding equation Cl t/> = <£ 12'
gives in terms of w every solution of the prohlem to reduce a given
matrix Cl to its canonical form. For if Cl' = 0, the most general
solution of the equation

reduces to

(f) = Oil}/,

where ij/ is the most general matrix commutative with 6, and w is
some particular value of </> satisfying the equation Cl = <£ 6 </>-1.
But since the solutions of this equation are all included in those of
the equation Cl <f> = <f> 6, if the constants in if/ are so taken that its
determinant (and consequently the determinant of <£) is not null,
(j> = w ij/ is the most general solution of the problem to reduce a
matrix to its canonical form.

If O and CI' are matrices of the same kind,* and such that for
any latent root g the increments of nullity of successive powers
of CI — g (or CI' — g) are severally equal to the nullity of O — g
(or of CI' — g), until a power is reached whose nullity is equal to
its vacuity, then the most general solution of the equation
CI <f> = <£ Ci' can he expressed in terms of certain arbitrary matrices
and of products of powers of CI and CI' less their latent roots. Thus,

let the latent roots of O (and of CI') be gt, g2, gt, respectively

of multiplicity mx, m2, .... m(', and suppose that the nullities of
^ — ffi> ^ — <72> etc. are m\, m'2, etc. From the supposed equality
in the increments of nullity of CI — glf etc., it follows that

m i in 2 Mi

are all integers. Let, now,

* That is, fl and n' are such that it is possible to find a matrix x t0 satisfy
the equation CI' = x G X" '•

OF ARTS AND SCIENCES. 55

/, (9) = {~gr - jr^rY1 (i^r - g^irY* ....

(i^gr - g~^~g^-1 (i^f - g^=~grYr+1 • • • •

/r (fr) /r far)

Then the most general expression for the matrix <£ satisfying the
equation O </> = <f> 12' is

4> = So'?"1^ - 9'i)'tl"p-1 «i Mi fl'i («' - ^)r}

+ 2o*-1{(0 - ^)^-r-1 «2 M2 Q", (fi' - ;72)'}

+ ....+ ^-'{(n - ^)M'-r-1n« M o'« («' - SO),

where M1} M2, .... Mj, are arbitrary matrices.

If O' = ft, the expression to which this expression for <£ reduces
gives the most general matrix commutative with Q.

If O' = 0, and the matrices M in the above expression for <f) are
so taken (as is possible) that the determinant of <f> is not null, then
the expression for <f> gives the most general solution of the reduc-
tion of the given matrix fi to its canonical form.

56 PROCEEDINGS OF THE AMERICAN ACADEMY

VI.

RESEARCHES ON THE VOLATILE HYDROCARBONS.

By C. M. Warren.

Communicated May 12, 1868.*

HI. — ON THE VOLATILE HYDROCARBONS IN PENNSYLVANIA

PETROLEUxM. — Part I.

The results recorded in this paper were obtained previously to
the publication of a memoir " On the Influence of -GH2 on the
Boiling-points in Homologous Series of Hydrocarbons," etc.,
which I had the honor to present to the Academy in 1864. f
In that memoir I had occasion, for a special purpose, to intro-
duce, among others, the formulae of the hydrocarbons that I had
separated from Pennsylvania petroleum, but omitting for the time
being the data from which these formulae were deduced, with the
intention to follow shortly after with another paper in which these
data would be given. Publication was at first delayed for an op-
portunity to repeat some of the analyses by means of my process
for combustion in oxygen gas,| (which is specially suited to the
analysis of volatile substances,) with the view to obtain more ex-

* The manuscript of this memoir was found among the author's papers
after his death. The article had been presented to the Academy by title at a
meeting held on May 12, 1868, and appears to have been written out in its pres-
ent shape at that time, with the possible exceptions that one or two brief foot-
notes may have been added subsequently, and that the style of naming some of
the compounds may have been changed. The author's motive for holding back
the communication — as indicated by brief marginal notes written in pencil
upon his manuscript — seems to have been based on a wish to make one or two
new analyses, and to repeat by a process of his invention a few determinations
of vapor density, in order that absolute justice might be done to Pelouze and
Cahours in his criticism of their work. Broadly considered, the delay appears
to have been a case of procrastination pure and simple, for there is evidence
that the author had never given up his intention of publishing the paper as it
now stands.

t Memoirs of the American Academy, (N. S) IX. 156.

f Proceedings of the American Academy, 1864, p. 251.

OF ARTS AND SCIENCES. 57

act results which might throw some light on the question raised
in that paper,* as to whether the 1st and 2d series there pre-
sented should he considered isomeric. For the same reason, it
seemed desirable also, before publication, that the relations of
these series should be further studied by at least a preliminary
examination of some of the more important chemical properties of
the different bodies which they comprise. With no immediate
prospect of being able to pursue these inquiries, — already so long
deferred from unavoidable causes, — it seems now advisable to
publish the results obtained, without relinquishing, however, the
hope of continuing the investigation.

Notwithstanding the fact, as above intimated, that some of the
results to be presented are not entirely satisfactory, they are pub-
lished in the belief that they are more nearly correct than the cor-
responding results that others have obtained in the investigation of
this petroleum; and will, therefore, contribute materially to our
knowledge of the bodies obtained therefrom. This belief is justi-
fied by the circumstance that the different constituents of the
petroleum were separated by a process far more searching and re-
liable than any distillatory process that had been applied to such
a mixture ; f hence, that the several bodies examined were obtained
in a state approximating much nearer to purity than seems possible
by any other method of fractional distillation yet devised. As a
natural consequence, some of the more important results that I
have obtained in the study of this petroleum differ essentially
from those of other investigators of the same material, notably
those of Pelouze and Cahours, whose researches are often quoted as
authority on this subject. $

Before proceeding to give the experimental results which it is
the special object of this paper to furnish, it may be of service,
and may excite additional interest in the subject, to recall briefly
some of the facts furnished in my former paper, and to specify
some of the more striking differences between my results and those
of the chemists above mentioned.

In the memoir first above referred to (pp. 166, 167), the hydro-
carbons that I have separated from this petroleum are classified

* See foot-note, page 167.

t " Process of Fractional Condensation," etc., Memoirs of the American
Academy, (N. S.) IX. 121.

t Comptes Rendus, LIV. 1211, LVI. 505, LVII. 62.

58 PROCEEDINGS OF THE AMERICAN ACADEMY

in three natural series, designated, provisionally, as 1st, 2d, and
3d series. The first two of these may be conveniently considered
as parallel series, since they exist as it were side by side, and in
fact extend through and naturally belong to the same portion of
the petroleum, and present, moreover, a nearly uniform difference
of boiling-point, viz. about 8° C. between any two corresponding
or opposite members of the two series, as will appear on inspection
of the tables. Both series, however, have in common the boiling-
point difference of about 30° between any two contiguous members,
corresponding to the common elementary difference of "GH2, as also
shown in the tables referred to. The members of the 3d series
have boiling-points ranging from 0° to 150°, and those of the 2d
series from about 8° to 128°.

In striking contrast with these results, Pelouze and Cahours
found in this portion of the petroleum but one series, or only
about one half the number of bodies that I obtained. We do not
differ, however, as to the general formula (C„H2n + 2) of the bodies
belonging to this portion of the petroleum. But in regard to the
boiling-point difference for the successive terms of the series,
which, as already stated, I have shown to be uniformly about 30°
in the £nH2n + 2 Series, we find in their results hardly an approxi-
mation to uniformity in this respect. On the contrary, their
boiling-point differences, corresponding to an elementary differ-
ence of -€H2, are observed to vary so widely as from 16° or 20°
to 38°.

Yet more remarkable is the circumstance that, above 150° (the
highest point reached by either of my first two series), in that
part of the petroleum embracing my 3d series, in which I find
only bodies of the general formula CnH2n, they find, on the con-
trary, none of these, but continue to obtain bodies which they
represent as having the same general formula as those belonging
to the more volatile portion of the petroleum.* They maintain that

* The temperatures here given relate, of course, either to isolated sub-
stances, or to sections of the petroleum considered as if composed exclusively
of those bodies whose true boiling points have been found to come within the
limits of temperature above indicated ; not ignoring the fact, however, that
during the process of separation, when applied to a mixture that includes all of
the three series, some of the 1st and 2d series come off in reality at tempera-
tures considerably above that indicated as the highest limit of these two series,
viz. 150° ; nor unmindful of the fact, on the other hand, that some of those
of higher boiling-point — members of the 3d series — are carried over with the

OF ARTS AND SCIENCES. 59

the whole liquid portion of the petroleum is made up of one con-
tinuous series, having the general formula -€„H2n + 2; and, more-
over, that the solid paraffines from this source belong also to this
series, of which at least there is much reason to doubt.

Concerning a natural product of great importance in itself and
in its relations, results so discordant as above indicated should
have a careful and impartial examination with reference to the
different conditions under which they were respectively obtained,
with the view to determine which should be regarded as the more
accurate. Having this purpose in view, and with the conviction
that the work done does not so much need repetition as to be un-
derstood, and believing that the facts that I have to present are
sufficient to establish at least the probability of the correctness of
the conclusions I have reached, it will be necessary, in the follow-
ing consideration of the subject, to make such further comparison
of their results with my own as the pursuit of the object defined
seems to require.

Examination of the Petroleum.

Of the Material employed. — Commercial Products from the

Petroleum.

In the investigation of this petroleum I have not operated
directly on the crude oil, but upon certain distillates obtained
from this on a manufacturing scale. Special care was taken to
procure these from a reliable source, and to obtain such as had not
been subjected to any chemical treatment; and also such, taken
collectively, as would fairly represent the natural product so far as
to include in sufficient quantity all of its constituents. A brief
description of these crude distillates, indicating their comparative
value as sources of supply of the different constituents, may not be
void of interest, and may be of service to such, especially, as may
have occasion to repeat any portion of the work. This remark is
suggested by a statement of Schorlemmer * with respect to one of
the members of my 1st series, viz. that boiling at 61°.3, that it
was not present in the petroleum that he worked upon. After the

vapors of the more volatile ones, at temperatures below their true boiling-
points, or within the range of the 1st and 2d series, their true or natural posi-
tion in the series not admitting of determination until, by the process of sepa-
ration, the bodies shall have attained a comparatively high degree of purity.
* Philosophical Transactions, 1872, Vol. CLXII. p. 116.

60 PROCEEDINGS OP THE AMERICAN ACADEMY

publication of my first memoir, above referred to, tbis chemist
appears to bave made a special search for these bodies, which were
entirely overlooked in his earlier research, and such of them
as he found he seems to have obtained in small proportion, — quite
the reverse of my experience. E. g., of the body boiling at 61°. 3,
which, as stated, he did not find, the proportion of my product, as
compared with that boiling at about 68°, was as 7 to 8.

In the earlier stage of the distillation, in the manufacture of
"illuminating oil" or " refined petroleum, " (a medium product,
amounting to some 70 per cent of the crude material,) there is ob-
tained, as is well known, a considerable quantity — frequently
about 15 per cent — of a colorless and highly volatile liquid, vari-
ously known in commerce as naphtha, spirits of petroleum, and,
improperly, as benzine. Although containing some of the sub-
stances that more especially characterize the heavier or medium
portion of the petroleum, the larger proportion of this naphtha is
composed of bodies whose boiling-points range from 0° to 150°,
these being the limits of my provisional 1st and 2d series, and is
therefore a convenient source from which these for the most part
may be obtained. Some manufacturers separate this naphtha, ei-
ther by a second distillation or during the distillation of the crude
petroleum, into two parts, a "light" and a "heavy naphtha."
The former of these is the product commercially known in the
United States as "Gasolene," which is more or less extensively
employed, mixed as vapor with atmospheric air, as a substitute
for coal gas. It was from this "gasolene" or " light naphtha, "
having the specific gravity 0.65 at 15° C, that the hydrocarbons
comprised in my 1st and 2d series were chiefly procured. Although
this product contains a larger proportion of some of the lower or
medium members of these two series, — as its low specific gravity
and high degree of volatility would indicate, — it also contains
considerable quantities of the higher ones; but the latter may be
obtained in greater abundance from the "heavy naphtha," and
in notable quantity also from the medium product described as
" illuminating oil, " from which to a considerable extent it may
be conveniently procured while operating to obtain the members of
the 3d series, of which this product is chiefly composed.

In the manufacture of these naphthas, a large portion of the two
most volatile constituents of the petroleum — those boiling at 0°
and 8° respectively — is generally allowed to escape condensation,
and to a considerable extent, also, the two next higher ones, boil-

OF ARTS AND SCIENCES.

61

ing at 30° and 38°. Since the first two here mentioned, when iso-
lated from those of higher boiling-points, are gases at the common
temperature, a mixture of these may be more readily obtained in
large quantity from a manufactory, by conducting the vapors from
the still into a condenser maintained at a low temperature, — be-
ing the product introduced by Dr. Henry J. Bigelow for a local
anaesthetic under the name of Rhigolene.* The large preponder-
ance, in this product, of these most volatile constituents of the
petroleum might be inferred from the fact, as stated by him, that
when continuously dropped on the bulb of a mercurial thermometer
evaporation is so rapid as to cause the mercury to fall to — 7°
within 5 to 10 seconds.

Of the Results of Fractional Condensation.
For convenience of reference I will here repeat, with slight mod-
ifications, some of the tables from my previous memoir. These
exhibit the three homologous series of hydrocarbons that I have
separated from the petroleum, together with their boiling-points,
the differences of boiling-point corresponding to an elementary
difference of -€H2, and their formulae, — the data for which are
given on the following pages.

Hydrocarbons from Pennsylvania Petroleum.
1. Marsh-gas Series.

Name of
Substance.

Butyl Hydride
Amyl
Hexyl "
Heptyl "
Octyl
Nonyl "

Formula.
€nH2„ + 2

Boiling-
point.

€4H10

0.0 1

€5H12

30.2

A^H

61.3

€7H16

90.4

€sHi8

119.5

€9H20

150.8

Elementary
Difference.

€H.2
€H2
€H2
€H2
€H-

Difference of

Boiling-point

found.

30.2

31.1

29.1
29.1
31.3

Range of Temper-
ature within
which Substance
all distilled.

1.5

0.8
1.0
1.0
0.8

150.8 -^ 5 = 30°.16
Average increment of boiling-point for the addition of CH2 = 30°. 16.

* Chemical News, 1866, XIII. 244.

t Ronald's determination.

62

PROCEEDINGS OF THE AMERICAN ACADEMY

2. Isomeric (?) with the Marsh-gas Series.

Name of
Substance.

Formula.
■CMH2n+2

Boiling-
point.

Elementary
Difference.

Difference of

Boiling-point

found.

Range of Temper-
ature within

which Substance
all distilled.

Iso-Butyl Hydride

€4H10

o

8-9

—

o

o

" Amyl

€5H12

37.0

€H2

29.0

0.4

" Hexyl "

■GoHi4

68.5

€H2

31.5

0.6

" Heptyl "

• €7H16

98.1

€H2

29.6

1.2

" Octyl

^8^18

127.6

€H2

29.5

1.5

119.6 -f 4

= 29°.9

Average incre

ment of bo

iling-point for the addition of CH2 = 29°.9.

3. Ethylene Series.

Name of
Substance.

Formula.

€nH2n

Boiling-
point.

Elementary
Difference.

Difference of

Boiling-point

found.

Range of Temper-
ature within
which Substance
all distilled.

Rutylene

Margarylene

Laurylene

^10^20

■GnH22

■G12H24

174.9
195.8
216.2

€H2
€H2

o

20.9
20.3

o
1.7

1.5

2.2

41.2 ~2 = 20°.6
Average increment of boiling-point for the addition of CH2 = 20°.6.

Having already given in one of the memoirs above referred to a
detailed description of the process devised for the separation of the
constituents of such complex mixtures of liquids as that under
consideration, and which was employed in this research, these
details are here omitted. I should state, however, that in con-
ducting the separations in this case, the same exhaustive method
was pursued as therein described.* By this treatment, the inter-

* Memoirs of the American Academy, (N. S.) IX. 130-134.

OP ARTS AND SCIENCES. 63

mediate small fractions lying between the prominent ones were
repeatedly and so thoroughly worked over as to prove the absence
of other bodies than those described, i. e. in quantities appreciable
by fractional condensation. I do not, however, ignore the fact
that small quantities of other bodies might be present and escape
detection. That any appreciable constituent of that part of the
petroleum worked upon was overlooked in this investigation is the
more improbable from the fact that, in consequence of the dis-
covery of the new series isomeric with the hydrides, vastly more
time and labor were given to these separations than are ordinarity
required, or than would have been necessary otherwise. The ex-
tremely small difference of boiling-point between the correspond-
ing or opposite members of these two parallel series has necessitated
a most thorough and critical examination, requiring a vast number
of redistillations, each extending over the whole range of frac-
tions,— a fraction being taken for every degree of temperature, —
and this extremely tedious process was continued until the small
intermediate fractions, as before stated, had become too small to
admit of being further operated upon; and until the boiling tem-
perature of the large fractions herein treated of had ceased to un-
dergo further change by this treatment. This course was deemed
indispensable, — regardless of the large expenditure of time in-
volved,— since nothing less could suffice to remove all doubt as
to the existence of the newly discovered series, and insure for the
different substances that degree of purity requisite for any satis-
factory study of their individual properties.

I have laid special stress on the circumstance here related, since
it appears, on comparison of my results with those of Pelouze and
Cahours, that they claim to have found one more body between
about 120° and 236° than I have been able to discover. Either I
have overlooked in my anal}rsis one constituent of the petroleum
between these limits of temperature, or they have described one
having no existence therein; in this connection, for obvious rea-
sons, my newly discovered series of isohydrides is of course not
taken into account. To facilitate a comparison of their results
with my own, as the latter are exhibited in the preceding tables, I
will here introduce the following table prepared by me for this
purpose.*

* At this date the nomenclature here employed may appear antiquated ;
but since this does not affect the intrinsic value of the paper, I have preferred
to let it pass through the press as written several years ago.

64

PROCEEDINGS OF THE AMERICAN ACADEMY

Tabular Statement of the Formulae and J3 oiling -points of the
Constituents of Pennsylvania Petroleum, as determined by
Pelouze and Cahours.

Name ol Substance.

Formula
(€„H2n + 2)

Boiling-
poiat.

Elementary
Difference.

Difference of

Boiling-point

found.

(Average.)

Hydride of Butyl

€4^0

0

5-10

—

0

Amyl

^5H12

30

€H2

22.5

" Caproyl

€tiHu

68

€H2

38.0

CEnanthyl

^7H16

92-94

€H2

25.0

Capryl

€gH18

116-118

€H2

24.0

" Pelargonyl

t/9Hi0

136-138

€H2

20.0

Rutyl

^-'10^22

160-162

€H2

24.0

u

^-/11**24

180-184

€H2

21.0

" Lauryl

€12H26

196-200

€H2

160

" Cocinyl

GlZ™-2»

216-218

€H2

19.0

" Myristyl

^14^30

236-240

€H2

21.0

<t ^^^—

^15^32

255-260

€H2

19.5

As their results, indicated by the above table, differ so widely
from mine, not only in regard to boiling-points in several instances,
but also in the important matters of vapor density and elementary
constitution corresponding thereto, as will be shown further on, it
is impossible for me to determine with any degree of certainty
which of the several bodies they describe should be chosen as the
one whose existence in the petroleum must be questioned; for
my results, I trust, will show conclusively that one of their num-
ber must be discarded, and that consequently the formula of the
rejected member would naturally fall to the one next above, and
the formula of this in turn to the next higher, and so on, changing
the formulae of all the higher members of their series. Since, how-
ever, they have not described a greater number of bodies within
the range of temperature embraced by my 3d series — the €nH2n
series — than were found by me, although we differ widely as to
their constitution; and since their boiling-points in this part of

OP ARTS AND SCIENCES. 65

the petroleum are less at variance with mine, I am induced to con-
sider that the spurious hody in question is more probably one of
the two lying between 120° (a point at which we agree very nearly
both as to boiling-point and vapor density) and 175°, the point at
which my 3d, or €„H2„ series, begins. It matters little which of
these it is, and we will therefore assume it to be the lower one of
the two, or their first above 120°, viz. that boiling at 136°-138°,
which they represent by the formula £9H20. This formula, it may
be observed, is the same that I have given to a body boiling at
about 150°, finding none intermediate between this and 127°; the
latter, however, is not of the same series, being isomeric with the
body boiling at 120°, having the formula -G8H18.

The question as to the existence in the petroleum of a body
whose boiling-point lies between the limits of temperature indi-
cated, viz. 127° and 150°, is seen to be of more importance when
it is considered, as above stated, that it involves the question as
to the constitution or correctness of the formula or formulae of the
higher member or members of the series; and especially so if it be
held that the -G„H2n + 2 series in petroleum, instead of terminating
at 150°, as I maintain, is really so extensive as alleged by Pelouze
and Cahours, — they having already assigned to it seven bodies of
boiling-points above 118°, the highest of which boils at 260°; and
assumed, as already stated, that this series goes on uninterrupted
to, and includes, the solid paraffines. For if, as I maintain, the
petroleum does not contain the body in question, and if the
•€„H2n + 2 series has the wide range which they assert, then it
must follow that the formulae assigned by them to these seven or
more bodies would each require the deduction of -€H2, and hence
that their determinations would become almost worthless, since so
great a discrepancy would indicate for the substances a degree of
impurity sufficient to destroy confidence in the results that they
obtained in the further study of these bodies. I have assumed, in
this consideration, that the lower members of the series have been
correctly determined, there being no disagreement between their
determination and my own of the formula — -€sH18 — of the body
boiling at 119°. 5 (11G0-118° by their determination), nor of the
formula? of the lower members of the series.

Trusting that a comparative examination of the results pre-
sented in this paper, giving due consideration to the fact of the
greater efficiency of the process employed in my proximate analjrsis
of the petroleum, will leave no room for doubt on the questions
vol. xxvu. (n. s. xix.) 5

66 PROCEEDINGS OF THE AMERICAN ACADEMY

presented, and will confirm the views above stated, I will now
proceed to give details of the elementary analyses, and of the ex-
periments to determine such of the physical properties of the indi-
vidual bodies as are usually relied upon to identify or characterize
bodies of this class. I would here state, however, once for all,
that, unless specially mentioned, no one of the bodies operated
upon had received any chemical treatment except that of boiling
with sodium.

Of the Analyses and Physical Properties of the different Bodies
separated from the Petroleum.

1. Butyl Hydride and Butyl Iso-Hydride = C4H10.*

My examination of butyl hydride and its isomeric associate in
the petroleum has been more limited than that of the other mem-
bers of the series to which they respectively belong. As these
bodies could at any time be readily obtained in larger quantity at
a manufactory, in the manner above described, I omitted to make
further use of the small quantities that I had incidentally col-
lected than to determine their boiling-points, and of one of them,
viz. iso-hydride of butyl, the specific gravity, which was found to
be 0.6107 at 0°. Ronalds has found the specific gravity of the
other, viz. hydride of butyl, to be 0.600 at 0°.

In the original publication of the above tables, the boiling-point
of butyl hydride was given, with an interrogation point, as 0°;
for although I had observed that a mixture of the two bodies be-
gan to boil at about this temperature, it was on theoretical consid-
erations that this precise figure was given, and, of course, a more
positive statement would not be justifiable. That this, however,
is at least very nearly its true boiling-point, has since been con-
firmed by Ronalds, t who has made a special study of the most
volatile part of the petroleum, and who states that it begins to boil
at 0°. It does not appear, however, that he made a better separa-
tion of the two bodies, for he failed even to detect the presence
of butyl iso-hydride, and could not therefore have made an attempt
to separate it. Moreover, he worked by the old method. Ronalds,
however, collected a liquid boiling between 6° and 8°; specific
gravity 0.6004, but did not regard it as a distinct body, but

* Studied in 1868 by E. Lefebvre, Jahresb., 1868, p. 329.
t Journal of the Chemical Society, London, 1865.

OF ARTS AND SCIENCES. 07

merely as a mixture of butyl hydride and amyl hydride, C5H12,
which latter boils at about 30°.

It is needless to remark that to call this a mixture, in the broad
sense that Ronalds has done, does not accord with my experience.
The boiling-point, 8°-9°, that I found for butyl iso-hydride was
the result of an actual determination in the usual manner. The
material employed for this purpose had been repeatedly and care-
fully distilled through my regulated condenser; but it had finally
become so reduced in quantity as to necessitate suspension of the
process of fractionation before the separation was so nearly com-
plete as is claimed for the bodies of higher boiling-point. Never-
theless, it is believed to have been sufficiently pure to justify the
conclusion — supported also by analogy — that there is a constit-
uent of the petroleum boiling at about 8° to 9°, as I had stated.
I would not, however, be understood to maintain that this body,
as obtained, contained no admixture of butyl hydride, or even of
amyl hydride, for doubtless it contained both of them to some ex-
tent. I only contend that probably neither was present in suffi-
cient quantity to materially, if indeed perceptibly, influence the
boiling-point, and consequently that the elevation of the boiling
temperature above 0°, or that of butyl hydride, was not due to the
presence of amyl hydride, as we should infer from Ronald's state-
ment, but rather to the fact that it was mainly composed of butyl
iso-hydride, which he overlooked.

I may remark in this connection that a similar view is held in
regard to the purity of the other bodies that I have separated from
the petroleum; although the purification of most or many of these
was carried to the extreme practicable limit, they doubtless still
remained mixtures, but probably in such relative proportions as to
admit of correct, or at least very nearly correct, determinations
of their boiling-points. That such was the probable condition of
these bodies is not merely a theoretical opinion based on my own
observations. The experiments of Berthelot * show that mixtures
of neutral liquids whose boiling-points differ by 20°-30°, being
mixed in such proportion that the least volatile amounts to 8 or
10 per cent, do not admit of separation by distillation under ordi-
nary pressure, and will frequently, if not always, be found to com-
port themselves like homogeneous substances.

Berthelot's results have since been confirmed by Alluard, f who

* Comptes Rendus, LVII. 430. t Comptes Rendus, LVIII. 84.

6'8 PROCEEDINGS OF THE AMERICAN ACADEMY

found that ether mixed with one tenth of its weight of bi-sulphide
of carbon, not only had a constant boiling-point, but that this was
the same as that of pure ether. He also made similar observations
on mixtures of bi-sulphide of carbon and alcohol, and alcohol and
water.*

In the case of a mixture of two liquid bodies whose physical
properties differ so little as those of the hydrides and iso-hydrides
under consideration, probably a larger proportion of the lesser
constituent of the mixture may be present without affecting the
boiling-point of the larger one, than was shown in the experiments
of Berthelot and Alluard; and, in such a case, it may be found
impossible to purify a body sufficiently for some of the require-
ments of an investigation. But the fact that the constituents of
such a mixture may be brought into such proportions by fractional
condensation as to give the true boiling-point of the larger con-
stituent, must nevertheless be regarded as of great importance in
many cases, since the boiling-point is frequently an invaluable
means of controlling the formulae in homologous series; and espe-
cially so when the body under examination contains so large an
admixture of foreign substance that the vapor density and ultimate
analysis cannot be relied upon, which might often occur. Evi-
dently these are considerations to be taken into account in passing
judgment upon the value of results of an investigation of a mix-
ture of liquids based on a proximate analysis by any method of
fractional distillation; and it cannot be too strongly maintained,
that constancy of boiling-point, even if considered only as an ap-
proximative indication of the degree of purity, should nevertheless
be regarded as of the highest importance, and scarcely less so that
the separations should be made under the most favorable condi-
tions for the removal of the largest possible amount of impurity, —
conditions which certainly cannot be claimed for the old process of
fractional distillation.

* I propose to make a series of experiments on mixtures of pure liquid sub-
stances in definite proportions, with the view to determine whether, or to what
extent, the observations of Berthelot and Alluard will hold true when a mix-
ture, of constant boiling-point, and inseparable by the old method, is distilled
through my regulated condenser; and at the same time to determine also, ap-
proximately, the degree of purity attainable by my method, as a test of the
capability of the process.

OP ARTS AND SCIENCES. 69

2. Amyl Hydride = C^H

12-

Specific gravity 0.6400 at 0°; 0.6275 at 14°. 2; 0.6269 at 15°;
0.6249 at 17°.*

Determination of Boiling-point. — The method employed in this,
and in all of the determinations of hoiling-points given in this
paper, unless some variation is specially mentioned, was precisely
the same as that described in detail in the memoir first above re-
ferred to, page 159, and following. As constancy of boiling-point
and accuracy of determination of the same are of so much impor-
tance in this investigation, and as I have deviated in some respects
from the usual method of taking boiling-points, attention is spe-
cially called to what is said in that memoir on this subject; more
particularly to the remarks on the question as to whether the ex-
periment should be conducted with the bulb of the thermometer in
the liquid or in the vapor. Some experiments there recorded bear-
ing on this question are also referred to.

In order to show more fully the degree of purity of the sub-
stances, and the degree of thoroughness and accuracy of the analy-
sis of the petroleum which this may indicate, I shall give in each
case the readings of the thermometer at stated intervals during the
distillation either of the whole, or very nearly the whole, of the
liquid employed in the experiment, taking a fair average of these
as the observed boiling-point. This, it will be observed, is a much
severer test of purity, and is attended with less liability to per-
sonal error, than the more common practice of simply noting the
temperature at which a certain degree of constancy of boiling-point
is observed, omitting to indicate the limits of the distilling tem-
perature. The custom here referred to has the additional objec-
tion, moreover, that it is liable to convey a wrong impression as to
the actual degree of purity of the liquid, — not giving sufficient
data to enable others to judge of this and of the accuracy of the

* It being too generally the custom, as I have remarked on a former occa-
sion, to determine the specific gravities of volatile liquids at the temperature
most convenient at the time of the experiment, without regard to uniformity
of practice, which is so highly desirable, I have been obliged, in order to make
a satisfactory comparison of other determinations with my own, to repeat the
determinations at the temperatures employed by the different observers. As
the results of these determinations occupy so little space, I am induced to insert
them, as they were all taken with great care, and by means of a specific gravity
bottle of the best construction for volatile liquids. A description of this bottle
is given in Vol. IX. (N. S.) p. 144, of the Memoirs of this Academy.

70 PROCEEDINGS OF THE AMERICAN ACADEMY

determination, — so desirable when dealing with mixtures, like
those of the hydrocarbons from petroleum, that cannot be made to
yield, by the common process, liquids having a constant boiling-
point, nor, properly considered, a very near approach to one, but
only a pretty long " boiling-space."

In the present experiment the readings of the thermometer were
as follows : —

Observed temperature of the liquid at commencement of distillation, 29°.5

8 minutes later, 29°. 7

10 " 29°.9

21 " 30°. 1

5 " 30°.3

At the latter temperature the liquid had distilled almost to dry-
ness; and at 31°, six minutes later, not a drop of liquid remained
in the retort. The duration of the experiment was 50 minutes,
and the range of distilling temperature 1°.5, or 0°.8, if we omit
the last, and doubtless least reliable, observation. As the ther-
mometer was doubtless directly influenced by the superheated re-
tort-bottom during the distillation of the last few drops of liquid,
the last observation is considered of no value except as furnishing
additional evidence of the high degree of purity of the substance,
i. e. for so volatile a body of this class, obtained by fractional dis-
tillation. That it should be otherwise disregarded is shown by
the fact that the bulk of the liquid passed over with so slight a
variation of temperature, viz. only 0°.4, from 29°. 7 to 30°. 1, dur-
ing the long interval of 31 minutes. The average of the first five
observations, or 29°. 9, is therefore taken as the observed boiling-
point; which, corrected for pressure and the upper mercurial col-
umn, becomes 30°. 1, being almost identical with the boiling-point
that Frank land originally found for this body. The latter circum-
stance, with other corroborative evidence, such as the fact that my
analyses gave almost invariably a somewhat larger percentage of
hydrogen for the members of my 1st series than for the correspond-
ing terms of the 2d (which may prove, however, merely accidental),
has led me, while somewhat in doubt on this point, to regard this
body and its homologues of the 1st series as the true hydrides of
the alcohol radicals, or marsh-gas series; and the 2d series, pro-
visionally, as the iso-hydrides of these radicals, — a term which
may be appropriately retained if further examination shall furnish
no stronger evidence of difference in constitution. This view is

OF ARTS AND SCIENCES. 71

strengthened further by the fact that other observers besides Frank-
land and myself have found the boiling-point of hydride of amyl
30°, or thereabouts; or that it would begin to boil at very nearly
this temperature, indicating at least the probability that it has not
a higher boiling-point, for the gaseous butyl hydride, the next
lower body of the series, would probably have been so completely
expelled from the liquid during the long-continued process of frac-
tionation that the little which might remain would not sensibly
lower the boiling-point of the amyl hydride. C. G. Williams*
found that amyl hydride from Boghead naphtha boiled between
30° and 40° ; and a preparation of the same from similar material
from cannel coal gave Schorlemmer t the boiling-point 39°-40° ;
but subsequently he found that a preparation from American petro-
leum boiled at 34°, — which comes nearer to Williams's first obser-
vation than to. the lower of his own previous observations; and
since he states that he obtained a larger quantity of this, which
would enable him to continue longer the process of fractionation,
and since a preparation from this petroleum would doubtless con-
tain less of contaminating substances that might influence the
determination, it may be inferred that his later determination is
probably the more reliable of the two. But Pelouze and Cahours %
make the boiling-point of this body from American petroleum ex-
actly 30°, agreeing precisely with my own determination and
with that of Dr. Frankland. Furthermore, Wurtz § states that
amyl hydride from amyl alcohol boils also at 30°.

The determinations above quoted having been made previously
to the publication of my petroleum series, probably neither of the
investigators, either of the coal or petroleum naphtha, had the re-
motest idea of the presence of a series isomeric with the hydrides,
and therefore made no special effort to separate them; || and since
these determinations were evidently made on mixtures containing
variable proportions, and in some cases a preponderating quantity,
of these isomeric bodies, the disagreement between their results
does not seem surprising, nor that the boiling-point should have

* Quarterly Journal of the Chemical Society, XV. 130.

t Journal of the Chemical Society, 1862, XV. 419.

\ Bulletin de la Socie'te' Chimique, 1863, p. 231.

§ Comptes Rendus, 1862, LIV. 387.

|| A re-examination by Schorlemmer has since confirmed my discovery of
this series. Proceedings of the Royal Society, XIV. 468; Annalen der Chemie,
CXXXV 269.

72 PROCEEDINGS OF THE AMERICAN ACADEMY

been placed so high as 39°, or about that of the iso-hydride itself.
In the absence of evidence, therefore, that the body described by
Frankland boiling at 30° is not of the series of hydrides, it seems
reasonable to take this, the one first described and best studied, as
typical of this series ; and to consider, for the present, those bodies
that correspond with this in regard to their boiling-points and
other properties, viz. those boiling at 0°, 60°, 90°, and 120°, re-
spectively, as also of the same series; and those boiling at 9°, 39°,
69°, and 129°, as a series of isomers, or iso-hydrides ; for it is well
known with regard to the best-studied of homologous series of liquid
bodies that, as a rule, a common boiling-point difference between
the contiguous members prevails throughout any given series; any
deviation from this being so exceptional as to justify a suspicion
of error.* Nevertheless, the series of hydrides is generally repre-
sented with some of the boiling-points of one series and some of
the other, while others do not agree with the true boiling-points
of either series. It is hoped that the results recorded in this paper
may serve to bring order out of this confusion.

Analysis.^

0.1935 grm. of the substance gave 0.5912 of carbonic acid, and
0.286G of water.

* Note Goldstein's late paper.

t The analyses given in this paper having been made, for the most part, pre-
viously to the working out of my process for combustion in oxygen gas, above
referred to, it is to be understood, unless otherwise stated, that they were made,
so far as relates to those boiling under 150°, by distilling the vapor of the sub-
stance into a column of ignited oxide of copper, and completing the combus-
tion in a stream of oxygen. This method, however, was not at first successful.
So long as I continued to follow the direction of Regnault to connect the bulb
with the combustion tube by means of a caoutchouc tube, I was unable to
avoid a loss of several per cent, occasioned, doubtless, by the escape of sub-
stance through the material of the connecting tube. That this was the proba-
ble source of error was shown by suspending a piece of this tubing in the vapor
of petroleum naphtha at the common temperature, the walls of the tube soon
acquiring two or three times their original thickness, from absorption of hydro-
carbon vapor. During an analysis, however, no change in the appearance of
the tubing was noticed, — any perceptible thickening being prevented by the
heat and exposure to air carrying away the vapor as fast as absorbed. To get
over this difficulty, I contrived a convenient method of making the connection
with the combustion tube by means of a cork. A tube, 4 or 5 inches or more
in length, with a small bulb blown in the centre, and with capillary ends, was
substituted for the ordinary bulb. By leaving the tube of sufficient length on
each side of the bulb, the same bulb could be repeatedly used, only requiring

OP ARTS AND SCIENCES. 73

Calculated.

Found.

Carbon C5 60 83.334

83.326

Hydrogen H12 12 16.666

16.448

100.000

997774

Determination of Vapor Dens

ity,

Temperature of balance

9°

Heigbt of barometer 761.86

mm. at 0°

Temperature of oil bath

128° '

Incremeut of balloon

0.2776

Capacity of balloon

235.5 c.c.

Density of vapor found

2.7642

Theory -€5H12 — 4 vols.

2.4932*

that the capillary ends should be drawn out anew for each analysis This
bulbous tube containing the liquid to be analysed was used in the following
manner. A cork fitting the combustion tube was perforated to fit one end of
the bulbous tube, and the latter tightly inserted in the perforation so that the
whole of the long capillary end projected beyond the cork. This end of the
bulbous tube was then introduced into the combustion tube, and the cork firmly
pressed into its place. The cork being a suitably flexible one, the end of the
capillary tube, at the proper moment, was readily broken off against the inner
surface of the combustion tube, simply by a lateral pressure against the outer
half of the cork.

The distillation of the material from the bulb was better controlled by
means of a heated copper bar, as described in my paper " On a Process of
Organic Elementary Analysis," etc , already referred to. When no longer a
trace of liquid remained in the bulbous tube, connection with the oxygen gas-
ometer was readily made bj' means of a caoutchouc tube, and communication
established by breaking off the capillary end within the caoutchouc connecting
tube by means of pliers against the sides of the tube. Before the latter was
done, however, the oxygen was turned on, in order to produce pressure from
behind, and thereby prevent a possible loss from passage of vapor backward.

When making several analyses in succession, the posterior end of the com-
bustion tube was generally found too hot at the close of an analysis to admit of
being so tightly clenched with the hand as is necessary in attaching the bulbous
tube ; and attempts to make a good connection in this manner under such cir-
cumstances were generally unsuccessful. To overcome this difficulty, I pro-
cured an iron clamp lined with cork, the lower half of which was attached with
screws to the top of the combustion furnace in such a position that the com-
bustion tube, at a convenient point near the end, would rest on the cork in the
lower half of the clamp. The upper half of the clamp being then laid on and
tightly screwed down, served to hold the tube so firmly that the whole force of
the hand could be applied to the cork, and thus insure a perfectly tight joint
without producing the slightest disturbance of the rest of the apparatus.

* C = 0.831 ; H = 0.0693. [Mem.] " Repeat this determination by my
process."

74 PROCEEDINGS OF THE AMERICAN ACADEMY

3. Amtl Iso-Htdkide = C5H12.
Specific gravity 0.6454 at 0° ; 0.6326 at 15° ; 0.6306 at 17°

Determination of Boiling-point.

Observed temperature of the liquid at commencement

of distillation 36°. 6

Observed temperature of the liquid 38 minutes later 3(5°. 6

" " " 20 " " 36°. 7

" " " 10 " " 36°. 7

Eight minutes later the liquid had all vaporized. The corrected
boiling-point was found to be 37°.

Analysis. — By combustion with cupric oxide in the manner de-
scribed under Hydride of Amyl, 0.1666 gnu. of the substance gave
0.5068 of carbonic acid, and 0.2482 of water.

Calculated.

Found.

Carbon

€5

60 83.334

82.965

Hydrogen

Hi2

12 16.666

16.555

100.000 99.520

Determination of Vapor Density.

Temperature of balance 8°. 5

Temperature of oil bath 129°

Height of barometer 778.8mm. at 0°
Increment of balloon 0.2255

Capacity of balloon 227.5 c.c.

Density of vapor found 2.514

Theory €5H12 = 4 vols. 2.4932

4. Hextl Hydride — C6H14.
Specific gravity 0.6762 at 0° ; 0.6638 at 15°.

Determination of Boiling-point.

Observed temperature of the liquid at commencement

of distillation 61°. 0

Observed temperature of the liquid 1 minute later 61°. 2

" " " 36 minutes " 61°. 2

Five mintes later it had distilled to dryness. The temperature
of the boiling liquid was, therefore, absolutely constant at 61°. 2

OF ARTS AND SCIENCES. (O

during the space of thirty-six minutes. Its corrected boiling-point
is 61°27.

Analysis 1. — 0.1808 grm. of the substance gave 0.5561 of car-
bonic acid, and 0.2G98 of water.

Calculated Found.

Carbon €6 72 83.72 83.884

Hydrogen H14 14 16.28 16.580

100.00 100.464

Analysis 2. — 0.226 grm. of the substance gave 0.6968 of car-
bonic acid, and 0.3291 of water.

Carbon 84.089

Hydrogen 16.181

100.270

Determination of Vapor Density.

Temperature of balance 17°

Temperature of oil bath 121°

Height of barometer 764 mm. at 10°
Increment of balloon 0.3666

Capacity of balloon 238 c.c.

Vapor density found 3.0528

Theory CBHU = 4 vols. 2.9735

5. Hextl Iso-Hydride = CGH14.
Specific gravity 0.689 at 0° ; 0.6772 at 15°.

Determination of Boiling-point. — Conducting this experiment
precisely as the preceding, the observed temperature of the liquid
at the commencement of distillation was 68°. 1, and it remained
absolutely constant during the long space of 52 minutes, distilling
down to a very small residue, which was left in the retort at this
temperature. The corrected boiling-point was found to be 68°. 5.

Analysis 1. — 0.1363 grm. of the substance gave 0.4214 of car-
bonic acid, and 0.194 of water.

Calculated. Found.

Carbon €8 72 83.72 84.43

Hydrogen H14 14 16.28 15.81

100.00 100.24

76 PROCEEDINGS OP THE AMERICAN ACADEMY

Analysis 2. — 0.1700 grrn. of the substance gave 0.5256 of car-
bonic acid, and 0.2412 of water.

Calculated.

Found.

Carbon

€fi

72 83.72

84.321

Hydrogen

H14

14 16.28

15.765

100.00 100.086

Determination of Vapor Density.
Temperature of balance 16°

Temperature of oil bath 129°

Height of barometer 762 mm. at 8°

Increment of balloon 0.8829

Capacity of balloon 262 c.c.

Density of vapor found 3.038

Theory €6H14 = 4 vols. 2.9737

6. Heptyl Hydride = C7H16.

Specific gravity 0.7183 at 0° ; 0.7065 at 15°.

Specific gravity after treatment with nitric acid 0.7033.

Determination of Boiling-point.

Observed temperature at commencement of distillation 88°. 7

10 minutes later 88°. 9

89°
89°. 1
89°. 3
89°. 7

n
a

a
a

17

a

a

13

a

a

5

a

a

10

a

a

having distilled quite to dryness. Applying the usual corrections
to the number 89°, the corrected boiling-point is found to be 90°. 4.
After treatment of a portion of this body with nitric acid, its cor-
rected boiling-point was 90°. 53. This experiment was made, how-
ever, on a very small quantity of liquid, and would hardly justify
the conclusion that the acid had really effected a change of the
boiling-point.

Analysis 1. — 0.2268 grm. of the substance gave 0.7031 of car-
bonic acid, and 0.3165 of water.

Calculated. Found

Carbon €7 84 84.00 84.55

Hydrogen H16 16 16.00 15.51

100.00 100.06

OP ARTS AND SCIENCES.

77

Analysis 2. — 0.2187 grin, of the substance gave 0.6766 of car-
bonic acid, and 0.3064 of water.

Calculated.

Found.

Carbon

€7

84 84.00

84.38

Hydrogen

Hi6

16 16.00

15.57

100.00

99.95

Determination of Vapor Density.

Temperature of balance 12°. 5

Temperature of oil bath 134°

Height of barometer 746 mm. at 6°
Increment of balloon 0.4383

Capacity of balloon 242 c.c.

Density of vapor found
Theory -€7H16 = 4 vols.

3.547
3.458

7. Heptyl Iso-Htrride = C7Hi6.

Specific gravity 0.7299 at 0°; 0.7184 at 15°. After treatment
with an excess of monohydrated nitric acid, specific gravity 0.7048
at 16°.

Determination of Boiling-point.

Observed temperature of the liquid at commencement

of distillation 96°. 6

Observed temperature of the liquid 10 minutes later 96°. 8

it tt tt 15 tt u 96o 9

" " «« 20 " " 97°. 2

Having had occasion to leave the experiment for a few moments at
this juncture, on returning ten minutes later it was found that
the liquid had distilled to dryness. The average of the observa-
tions 96°. 8 and 97°. 2 is 97°. Applying the proper corrections,
we find the corrected boiling-point to be 98°. 1.

After treatment of a small portion of this oil with monohydrated
nitric acid, its corrected boiling-point was then 97°. 85; but, as in
the last experiment, the quantit}' of oil operated upon was too
small to admit of making a very exact determination.

78

PROCEEDINGS OF THE AMERICAN ACADEMY

Analysis. — 0.2073 grin, of the substance gave 0.6469 of car-
bonic acid, and 0.2862 of water.

Calculated.

Found.

Carbon

€7

84 84.00

85.11

Hydrogen

H16

16 16.00

15.34

100.00

100.45

Determination of Vapor Density.

Temperature of balance 17°

Temperature of oil bath 138°. 5

Height of barometer 763.4 mm. at 9°
Increment of balloon 0.4236

Capacity of balloon 228.5 c.c.

Density of vapor found
Theory -€7H16 = 4 vols.

3.546
3.389

8. Octtl Hydride = C8Hi8.
Specific gravity 0.7374 at 0° ; 0.7262 at 15°.

Determination of Boiling-point. — The quantity of liquid at my
disposal for this experiment was considerably smaller than that
employed in the determinations above detailed; therefore, instead
of using a retort, the distillation was made from a large, long-
necked bulb. Since in this case the whole of the mercury was
situated below the cork, and surrounded by the hot ascending
vapors, no correction for the mercurial column is required.

Observed temperature of the liquid at commencement

of distillation 119°. 1

Observed temperature of the liquid 5 minutes later 119°. 2
" " " 10 " " 119°. 4

U u a 2 " " 119°. 6

a a << 3 u u 120°

At the latter point it had distilled nearly to dryness. This de-
termination was made under normal atmospheric pressure, and
therefore requires no correction. Taking the average of the five
observations, we find the boiling-point to be 119°. 5.

OP ARTS AND SCIENCES.

79

Analysis*
Determination of Vapor Density
Temperature of balance

Temperature of oil bath
Height of barometer
Increment of balloon
Capacity of balloon

Density of vapor found
Theory -€8H18 = 4 vols.

12°

198°
777 mm. at 9°
0.3889
215.5 c.c.

3.992
3.9425

9. Octyl Iso-Htdride = C8H18.
Specific gravity 0.7516 at 0° ; 0.7430 at 15°.

Determination of Boiling-point. — This experiment was con-
ducted in the manner described under octyl hydride, and for the
same reason there stated. Atmospheric pressure normal.

Observed temperature of the liquid at commencement

of distillation
Observed temperature of the liquid 10 minutes later

a a (< FJ a a

a
u

4
6

126°. 8
127°. 0
127°. 2
127°. 4
129°. 1

Average boiling-point 127°. 6.

Analysis.^
Determination of Vapor Density.

Temperature of balance

13°

Temperature of oil bath

211°

Height of barometer

777 mm. at 9°

Increment of balloon

0.3662

Capacity of balloon

212 c.c.

Density of vapor found

3.9900

Theory -€8Hlg = 4 vols.

3.9425

* A memorandum written by the author in pencil on the margin of his MS.
reads, after the word Analysis, " Not made, August, 1868."

t A note by the author reads: "Analysis not yet made, August, 1868."
Another memorandum reads : " Storer and \V. [in their memoir on the Exam-

80 PROCEEDINGS OF THE AMERICAN ACADEMY

10. Nontl Hydride = C9H20.
Specific gravity 0.7555 at 0° ; 0.7447 at 15°.

Determination of Boiling-point.

Observed temperature of the liquid at commencement

of distillation 148°. 7

Observed temperature of the liquid 15 minutes later 148°. 7

" " " 15 " " 148°. 9

" " " 5 " " 149°. 1

a k a 13 " " 149°. 4

u a a 2 " u 149°. 7

Average of observations 149°. 2. Corrected boiling-point 150°. 6.
Average of two determinations 150°. 8.

Analysis. — 0.1841 grin, of the substance gave 0.5765 of carbonic
acid, and 0.2526 of water.

Calculated. Found.

Carbon £9 108 84.375 85.40

Hydrogen H20 20 15.625 15.24

100.000 100.64

Determination of Vapor Density.

Temperature of balance

18°. 5

Temperature of oil bath

220°

Height of barometer

756.3 mm.

, at 17°

Increment of balloon

0.4649

Capacity of balloon

234 c.c.

Density of vapor found

4.460

Theory C9H20 = 4 vols.

4.426

ination of a Hydrocarbon Naphtha, obtained from the products of the Destruc-
tive Distillation of Lime-soap, Memoirs of the American Academy, 1865 (N. S.),
IX. 177] say H[ydride] of Cfapryl] boils at 128°, near bottom of page 195,
and elsewhere ? [i. e. page 194]. Perhaps I should call the ' 8 bodies ' [viz. those
boiling at 8°, 38°, and so on] hydrides, and the ' 10 bodies ' [boiling at 0°, 30°, etc.]
iso-hydrides? See Schorlemmer's late work, and compare with Wurtz's bodies
from amyl alcohol." It appears, however, that this hesitancy was but momen-
tary, for, as is to be seen above, on pages 70, 71, he finally accepted Frank-
land's hydride of amyl, boiling at 30°, as the prototype of the normal hydrides,
and relegated the substance boiling at 128° to the second series, of which it is
the last term. Note by F. H. Storer.

OF ARTS AND SCIENCES. 81

•€„H2n Series.

1 RUTTLENB = C10H20.

Specific gravity 0.7703 at 0°; 0.7598 at 15°.

1. Determination of Boiling-point. — By the thermometer em-
ployed, water was found to boil at 101°. 1.

Observed temperature of liquid at commencement of

distillation 172°. 5

Observed temperature of liquid 7 minutes later 172°. 7

a a a g it a 173°

it

a

It

5

a

tt

173°. 3

a

it

a

5

a

a

173°. 7

it

u

tt

2

it

a

174°

Had distilled nearly to dryness. Taking the average of the six
observations, and applying the proper corrections for pressure and
the upper mercurial column, and also deducting l°.l for the error
of the thermometer, the corrected boiliug-point is found to be
174°. 9.

2. Determination of Boiling-point. — By the thermometer em-
ployed water boiled at 100°. 5. This experiment was conducted
precisely as the last, and the material employed was the same.

Observed temperature of liquid at beginning of dis-

tillation

172°. 3

Observed temperature of liquid

5

minutes later

172°. 5

a it a

13

a

a

172°. 8

tt a u

22

a

n

173°

a a u

10

a

a

172°. 9

a (i a

10

it

a

172°. 9

a a a

5

a

a

173°

Five minutes later had distilled nearly to dryness, the tempera-
ture having risen to 173°. 8. Taking 173° as the observed boiling-
point, and making the proper corrections for pressure and the
mercurial column, and also deducting the error of the thermom-
eter, 0°.5, gives 175°. 3 as the corrected boiling-point.

VOL. XXVII. (n. s. xix.) 6

82 PROCEEDINGS OP THE AMERICAN ACADEMY

Analysis 1. — 0.1257 grin, of the substance gave 0.3951 of car-
bonic acid, and 0.1713 of water.

Calculated.

Found.

Carbon

"Gio

120 85.71

85.720

Hydrogen

H20

20 14.29

15.139

100.00 100.859

Analysis 2. — 0.2689 grm. of the substance gave 0.8398 of car-
bonic acid, and 0.3577 of water.

Calculated.

Found

Carbon

"tio

120 85.71

85.18

Hydrogen

H20

20 14.29

14.78

100.00 99.96

Determination of Vapor Density.

Temperature of balance 18°

Temperature of oil bath 236°

Height of barometer 757.4 mm. at 17°
Increment of balloon 0.5743

Capacity of balloon 249 c.c.

Density of vapor found 5.066

Theory €i0H20 = 4 vols. 4.843

2. Margarylene = CnH.2i.
Specific gravity, 0.7822 at 0° ; 0.7721 at 15°.

Determination of Boiling -point.

Observed temperature of liquid at commencement of dis-
tillation 192°. 5
Observed temperature of liquid 3 minutes later 192°. 7

{( a a £J a u 193°

« u u 10 u u 193°. 5

Five minutes later the bottom of the retort ha^ become nearly
dry, the temperature having reached 194°. 5. The average of the
first four observations is 193° ; and the corrected boiling-point
195°. 4. A second determination, by another thermometer, gave
the corrected boiling-point 196°. 2; the average of the two deter-
minations being 195°. 8.

OF ARTS AND SCIENCES. 83

Analysis 1. — 0.197 grm. of the substance gave 0.6183 of car-
bonic acid, and 0.2624 of water.

Calculated. Found.

Carbon €„ 132 85.71 85.60

Hydrogen H22 22 14.29 14.80

100.00 100.40

Analysis 2. — 0.1997 grm. of the substance gave 0.6248 of car-
bonic acid, and 0.2633 of water.

Calculated.

Found.

Carbon

€u

132 85.71

85.33

Hydrogen

H22

22 14.29

14.65

100.00 99.98

Determination of Vapor Density.

Temperature of balance 14°. 5

Temperature of oil bath 250°

Height of barometer 767 mm. at 13

o

Increment of balloon 0.6227

Capacity of balloon 247.5 c.c.

Density of vapor found 5.480

Theory €nH22 = 4 vols. 5.327

3. Laurylene = C12H24.

Specific gravity 0.7905 at 0° ; 0.7804 at 15°.

1. Determination of Boiling-point. — By the thermometer
employed, water boiled at 100°. 5.

Observed temperature of the liquid at commencement of

distillation 212°

Observed temperature of the liquid 16 minutes later 212°. 3
a u a 9 a (i 212°. 7

<( (( u 4 a a 213°

Three minutes later the boiling-temperature was 214°, having
distilled nearly to dryness. The average of the first five observa-
tions is 212°. 5. Deducting the error of the thermometer, 0°.5,
and making the usual corrections for pressure and the upper column
of mercury, the corrected boiling-point is found to be 216°. 8.

84

PROCEEDINGS OP THE AMERICAN ACADEMY

2. Determination of Boiling-point. — The conditions of this ex-
periment were the same as the last, with the exception that by the
thermometer employed, water boiled at 101°. 1.

Observed temperature of the liquid at beginning of

distillation
Observed temperature of the liquid 5 minutes later

3

a

a

a

a

5

4

u
((

it

a
(i

210°. 3
210°. 7
211°
211°. 5
212°

Had distilled nearly to dryness at 212°5. Average of the six
observations, 211°; corrected boiling-point, 215°. 5. Average of
both determinations, 216°. 2.

Analysis 1. — 0.1401 grm. of the substance gave 0.4349 of car-
bonic acid, and 0.1872 of water.

Calculated.

Found

Carbon

€12

144 85.71

84.66

Hydrogen

H24

24 14.29

14.85

100.00

99.51

Analysis 2. — 0.1934 grm. of the substance gave 0.608 of car-
bonic acid, and 0.2551 of water.

Calculated.

Found.

Carbon

"€■12

144 85.71

85.74

Hydrogen

H24

24 14.29

14.66

100.00

100.40

Determination of Vapor Density.

Temperature of balance 12°. 5

Temperature of oil bath 274°

Height of barometer 762.6 mm. at 4°
Increment of balloon 0.6905

Capacity of balloon 253 c.c.

Density of vapor found
Theory, Ci2H24 = 4 vols.

6.090
5.812

OP ARTS AND SCIENCES.

85

Having already given tables of the boiling-points, — the deter-
minations of which are above detailed, — with such deductions and
remarks as seemed appropriate, I will now proceed to treat the
other results in a similar manner. A comparison of these results,
which the tables will greatly facilitate, will bring to view some
interesting relations.

TABLE I. — Shoicing the Difference of Specific Gravity corresponding to Dif-
ference of Boiling-point of the Bodies obtained from Pennsylvania Petroleum,
arranged in the Order of the Boiling-points, regardless of Serial Classification or
Elementary Difference ; and also showing the Differences of Specific Gravity at
0° and 15°.

Name.

Formula.

Boiling-
point.

Specific

Gravity

at (P.

Differ-
ence of

Boiling-
point.

0

Differ-
ence of
Specific
Gravity.

Specific
Gravity
at 15°.

Difference

of Sp. Gr.

at 0"> and

15°

Butyl Hydride

C4H10

0.0*

0.6000*

—

—

—

" Isohydride

it

8-9

0.6107

8.5

0.0107

0.5967t

0.0104t

Amyl Hydride

C5H12

30.2

0.6400

21.3

0.0293

0.6269

0.0131

" Isohydride

St

37.0

0.6454

6.8

0.0054

0.6326

0.0128

Hexyl Hydride

C6H14

61.3

0.6762

24.3

0.0308

0.6638

0.0124

" Isohydride

it

68.5

0.6893

7.2

0.0131

0.6772

0.0121

Heptyl Hydride

C7H16

90.4

0.7183

21.9

0.0290

0.7065

00118

" Isohydride

u

98.1

0.7299

7.7

0.0116

0.7184

0.0115

Octyl Hydride

C^is

119.5

0.7374

21.4

0.0075

0.7262

0.0112

" Isohydride

<<

127.6

0.7516

8.1

0.0142

0.7430

0.0086

Nonyl Hydride

C9H20

150.8

0.7555

23.2

0.0039

0.7447

0.0108

Rutylene

C10H20

174.9

0.7703

24.1

0.0148

0.7598

0.0105

Margarylene

L/l l-tloo

195.8

0.7822

20.9

0.0119

0.7721

0.0101

Laurylene

C^oH24

216.2

0.7905

20.4

0.0083

0.7804

0.0101

Average differe

nee of bi

nling-point betwi

?en the corresponding hj

rdrides

and isohydrides 7'

3.7 nearly

7.

* Ronald's determination.

t Calculated.

86

PROCEEDINGS OF THE AMERICAN ACADEMY

TABLE II. — Showing the Difference of Specific Gravity at 0° corresponding to
the Common Difference of about 30° between their Boiling-points, and to the Ele-
mentary Difference of CH2 in the Series of Hydrides.

Name.

Formula.

Boiling-
point.

Specific
Gravity.

Elemen-
tary Dif-
ference.

Difference
of Boiling-
point.

Difference

of Specific

Gravity.

Butyl Hydride

C4H10

0.0*

0.6000*

—

—

—

Amyl

C5H12

30.2

0.6400

CH2

30.2

0.0400

Hexyl

C6H14

61.3

0.6762

CH2

31.1

0.0362

Heptyl **

C7H16

90.4

0.7183

CH2

29.1

0.0421

Octyl

CsH18

119.5

0.7374

CH2

29.1

0.0191

Nonyl

C9H20

150.8

0.7555

CH2

31.3

0.0181

Average differ*

jnce of boiling-poin

t 30°.16.

« a

specific grai

j\ty 0.0311

tt tt

n t

below

100° of boiling-point, 0.0394;

and above 10(

)°, 0.0186.

TABLE III. — Showing the Difference of Specific Gravity at 0° corresponding
to the Common Difference of about 30° between their Boiling-points, and to the
Elementary Difference of CH2 in the Series of Isohydrides.

Name.

Formula.

Boiling-
point.

Specific
Gravity.

Elemen-
tary Dif-
ference.

Difference
of Boiling-
point.

Difference
of Specific
Gravity.

Butyl Isohydride

C4H10

8-9

0.6107

—

—

—

Amyl

C5Hi2

37.0

0.6454

CH2

29.5

0.0347

Hexyl "

QH14

68.5

0.6893

CH2

31.5

0.0439

Heptyl

C7H16

98.1

0.7299

CH2

29.6

0.0406

Octyl

Q^g

127.6

0.7516

CH2

29.5

0.0217

Average difference of boiling-point, 30°.03.

" " specific gravity, 0.0352.

below 100° of boiling-poin
Difference of specific gravity above 180° of boiling-point, 0.0217.

t, 0.0397.

* Ronald's determination.

OF ARTS AND SCIENCES.

87

TABLE IV. — Showing the Difference of Specific Gravity at 0° correspondinq
to the Common Difference of about 20° between the Boiling-points, and to the
Elementary Difference of CH.2 in the CnH2n Series.

Name.

Formula.

Boiling-
point.

Specific
Gravity.

Elemen-
tary Dif-
ference.

Difference

of Koiling-

point.

Difference

of Specific

Gravity.

Rutylene

Margarylene

Laurylene

Cio"20
^11 22
Cl2**24

174.9
195.8
216.2

0.7703
0.7822
0.7905

CH2
CH2

20.9
20.4

0.0119
0.0083

NOTE ON A MEMOIR BY C. SCHORLEMMER.

There was found among Warren's papers, in the same portfolio
with the manuscript of the foregoing memoir, a printed copy of a
memoir " On the Normal Paraffins " (taken from the Philosophical
Transactions, 1872, Vol. CLXXIL), which had been presented to
Warren by its author, Dr. Schorlemmer. Upon the last page of
this presentation copy Warren had written in pencil some memo-
randa which, under the peculiar circumstances of the case, seem
to be worthy of being put upon record.

For the sake of clearness, page 123 of Schorlemmer's memoir is
here copied, in quotation marks, together with the memoranda
which stand written upon that page of the memoir in Warren's
handwriting.

It is to be observed that both the side-note, at the left of the
tabular matter, as printed on the next page, and the column of
figures headed "Difference found," at the right of the table, were
written by Warren. The asterisk also, affixed to the word
"Butane' in the table, and the foot-note to which this asterisk
refers, are copied from Warren's memoranda.

88 PROCEEDINGS OP THE AMERICAN ACADEMY

Homologues of Marsh Gas.

" Boilin

g-points.

Mean

Calcu-

Difference."

Difference found.

found.

lated.

[

"CH4

Methane

C2H6

Ethane

C3H8

Propane

37° to 39°, p. 114

C4H10

Butane*
Pentane

1°

38

1°

38

37

37

600 c.c. 97°.6 to ■

1

33 = 37-4

32 37-2 = 5

98°. Remainder '

r C6H14

Hexane

70

71

98°to99',p 121 \

29 = 33-4

29

C7H16

^8 Hl8

Heptane
Octane

99
124

100
125

25 = 29-4

25

C12H26

Dodecane

202

201

4X 19
4 X 19 "

ClfiHoj

Hecdecane

278

278

"In calculating the boiling-points, it was assumed, as appears
to be the case, that the difference decreases regularly by 4 until it
reaches the well known difference 19°."

* This Butane, C4H10) corresponds to the first memher of my first series,
which I call the normal hydrides of the alcohol radicals, the series above given
being isomeric with the hydrides.

According to my observations " Butane " should boil at about 8° to 9°, and its
isomeride at 0° instead of 1°. Taking 8° to 9° as the boiling-point of Butane,
the difference of boiling-point between it and " Pentane " would be 29° to 30°.

Taking 29° to 30° as the starting point for his calculated differences, and
deducting 4° successively, we have

29° to 30° - 4° = 25° to 26° Pentane and Hexane.
25° to 26° - 4° = 21° to 22° Hexane and Heptane.
21° to 22° - 4° = 17° to 18° Heptane and Octane.

OP ARTS AND SCIENCES. 89

VII.

NOTE ON A CRITICISM OF THE AUTHOR'S APPAR-
ATUS FOR FRACTIONAL CONDENSATION.*

By C. M. Warren,
Professor of Organic Chemistry, Massachusetts Institute of Technology.

The supplement of the American edition of the Chemical News
for February, 1869, contains an article on ''Cracking of Petro-
leums," hy the editor of the supplement, which closes with the
following paragraph : —

" In conclusion, we offer the suggestion to those who analyze oils
hy fractional distillation that they take pains to avoid the condi-
tions which favor cracking; by not observing such caution the
analyses of petroleums hitherto made have generally been vitiated,
in fact, very many have been worthless. Perhaps it is not possible to
avoid all the error that may arise from cracking, yet it may easily
be brought so low as to be insignificant. Of the apparatus which
has been devised for fractional distillation probably the one least
suitable for petroleums and other unstable liquids is that of Prof.
C. M. Warren. Warren's still probably answers well enough for
alcohols, essential oils, and the benzole series, but cracking can
scarcely be avoided when it is used for petroleums."

I am induced to notice the above criticism from the fact, to which
it recalls my attention, that the question of adaptability for the
separation of bodies more or less liable to decomposition by heat in
distillation, as compared with that of the common forms of distilla-
tory apparatus, was not specially considered in my memoir descrip-
tive of my process,! an omission which, it now appears, it might
have been better not to have made. It was not, however, from

* It would appear that this article was written in 1869. Two manuscript
copies of it were found among the author's papers after his death, viz. a rough
draft, and a fair copy ready for the printer's hands. The latter is here printed,
without change.

t Memoirs of the American Academy, 1864 ; American Journal of Science,
1865; Chemical News, 1865.

90 PROCEEDINGS OF THE AMERICAN ACADEMY

oversight that this was omitted, hut because it was thought that
no one could fail to see. on a moment's reflection, that the condi-
tions to which liquids are subjected in my apparatus, so far as
these may be of a nature to affect the liability to decomposition,
are quite the same as those attending fractional distillation by the
common process. It was therefore deemed sufficient to make no
further allusion to this matter than was done, indirectly, in recom-
mending my process for the separation of "bodies not decomposed
by heat in distillation " (p. 134 of the original memoir), clearly
implying that I did not regard it as faultless for the opposite class
of substances; and sufficient, it would seem, to put any one on his
guard who would make such use of it. Nevertheless, as I hold that
my process introduces no new condition favorable to decomposition,
even of bodies liable to partial change of this nature during distil-
lation, I do not hesitate to recommend it also as preferable to the
old process for this very class of substances, — when distillation
cannot be altogether avoided, — since the length of time required
to effect an equal or better separation may thereby be very much
shortened, and consequently the aggregate amount of decomposition
materially and proportionately lessened. But in operating upon
such substances it would be unadvisable to continue the process
longer than absolutely necessary to obtain the best approximation
to the desired result which the nature of the material would admit
of; and the same is of course true of the old process.

Not to enter into much detail, it may be stated that the only
essential difference between my apparatus and that in common use
for fractional distillation consists in the elevated condenser which I
interpose between the retort and the ordinary condenser, discharg-
ing itself backward into the retort, its temperature being regulated
by a separate flame, and maintained a few degrees (more or less,
according to the nature or purity of the substance to be distilled)
below the temperature of the retort.

In other forms of apparatus, there being no regulated condenser
to effect a separation of the mixed vapors that escape from the re-
tort, the whole of these go forward and are condensed together, the
resulting liquid falling into the receiver.

Both in my process and in the common process the liquid in the
retort is simply maintained in a state of ebullition under atmos-
spheric pressure; consequently it is no more favorably conditioned
for decomposition, in respect to temperature, in the one case than
in the other.

OF ARTS AND SCIENCES. 91

The elevated condenser being kept at a lower temperature than
that of the retort, it seems needless to say, has no effect to raise
the temperature of the latter, hut, on the contrary, holds it in
check; and by proper management may serve to secure the condi-
tions most favorable for taking off the largest possible quantity of
the most volatile constituent at any time present, and this at the
lowest possible temperature, not only of the vapor to be collected,
but also of the liquid in the retort, — operating therefore advanta-
geously, rather than unfavorably, with respect to decomposition.
And yet I suspect, as he does not specify, that this is the identical
feature of my process — being its chief or only distinctive feature —
which has occasioned nry critic's misconception with regard to the
utility of the apparatus. It would evidently require a considera-
bly longer time to distil a given quantity of a mixture of liquids
of different boiling-points in my apparatus, if used as recom-
mended for stable liquids, than in the common form, since in a
single operation the larger part of the mixture is in reality many
times condensed and re-distilled. Can this be his stumbling-block,
— that he has not taken into consideration the relative amount of
actual work (not measurable, however, by the quantity of liquid
distilled, but by the degree of purity of the products obtained) that
may be done with this apparatus in a given time as compared with
the common apparatus?

If the liquid is not subjected to a higher temperature in the one
apparatus than in the other, it is evident that superiority on the
score of decomposition must be awarded to the one capable of giv-
ing the best results in the shortest space of time, since the amount
of decomposition must be proportional to the time occupied. If
objection is made to the repeated condensation and re-distillation
that take place in my apparatus, I have only to say that this is a
necessary condition of any effective process of fractional distilla-
tion; and if, to avoid cracking, this condition must be abandoned,
and the vapors, as they rise laden with impurities, are immediately
condensed in the receiver, then must fractional distillation itself
be abandoned as a worthless process.

It has probably escaped my critic's scrutiny that my apparatus
does not require to be employed in precisely the manner that I
recommended for stable liquids; and a judicious chemist would
modify the conditions to suit the nature of the material to be ex-
amined, — I refer to the adjustment of the temperature of the ele-
vated condenser. In operating on perfectly stable liquids, I have

92 PROCEEDINGS OP THE AMERICAN ACADEMY

found it advisable to keep the elevated condenser at as low a tem-
perature as would permit the vapor of the most volatile liquid to
pass through it; for in proportion as its temperature is higher
than this, the product will contain a larger quantity of the less
volatile constituents ; and if the temperature he allowed to equal
that of the retort, the conditions of the experiment would not
differ essentially from ordinary distillation, except that friction,
from contact of the vapor with the sides of the worm during its
passage through the elevated condenser, might give it some slight
advantage. Between these two extremes of temperature for the
elevated condenser, therefore, it may he adjusted suitably for any
unstable liquid requiring and admitting purification by distilla-
tion, since the time required to distil a given quantity of liquid
by this process may be shortened, other things equal, in propor-
tion as the temj)erature of the elevated condenser is raised nearer
to that of the retort; and by shortening the time, other condi-
tions the same, decomposition, as said before, is proportionately
lessened.

I might give the details of many experiments to prove the supe-
riority above claimed for my apparatus, for it has given me reliable
results under the most varied conditions; but this does not seem to
be required. I trust that the foregoing remarks will be sufficient
to lead any one who may have questioned the adaptability of my
apparatus for the class of substances now under discussion to view
it in a different light.

OF ARTS AND SCIENCES. 93

VIII.

CONTRIBUTION FROM THE SALISBURY LABORATORY OF
THE WORCESTER POLYTECHNIC INSTITUTE.

ON THE FORMATION OF THE ANHYDRIDES OF BEN-
ZOIC AND SUBSTITUTED BENZOIC ACIDS.

By George D. Moore and Daniel F. O'Regan.

Presented by Professor L P Kinnicutt, April 13, 1892.

By the action of phosphoric anhydride upon benzoic acid and
an excess of benzol at 180-200°, Kollarits and Merz * obtained ben-
zophenone. The course of the reaction is shown by the following
equation :

C6H5COOH + C6H6 = C6H5COC6H5 + H20.

The same result was also obtained when, instead of benzoic acid,
benzoic anhydride was employed :

C6H5C0

) 0 + 2 C6H6 = 2 C6H5COC6H5 + H20.
C6H5C0

In a second paper f on this subject, the same authors state that
the formation of benzoic anhydride may possibly precede that of
benzophenone, and add that, if such is the case, benzophenone must
be formed by the direct action of benzoic anhydride upon benzol,
even in absence of phosphorpentoxide. This last result they were
unable to effect, even at temperatures ranging as high as 300°.
Similar negative results were likewise obtained when toluol was
employed instead of benzol. They therefore conclude that ben-
zophenone is the product of the direct action of phosphorpentoxide
upon benzoic acid and benzol.

The following experiments were undertaken with a view to
studying more carefully the conditions of possible formation of

* Zeitschr. fur Chemie, 1871, p. 705. Berichte, V. 447.
t Berichte, VI. 537.

94 PROCEEDINGS OP THE AMERICAN ACADEMY

anhydrides as intermediary products in the synthesis of ketones
from benzoic and substituted benzoic acids and hydrocarbons. If
anhydrides are formed at all, it is reasonable to suppose that the
reaction takes place at a temperature comparatively lower than
that required for the ketone condensation; and we find that this
is in fact the case.

I. Action of Phosphorpentoxide upon Benzoic Acid in an

Excess of Benzol.

10 grams of benzoic acid, previously melted, pulverized, and thor-
oughly dried, were dissolved on the steam bath in about 200 c.c.
of dry benzol, 10 grams phosphorpentoxide added to the hot so-
lution, and the whole boiled under a reverse condenser for about
four hours. The phosphorpentoxide did not appear to dissolve,
but settled to the bottom of the flask in the form of an amorphous,
gelatinous mass, which became gradually darker, until at the end
of the operation, it was nearly black.

The supernatant benzol solution was of a light amber color. It
was filtered hot from the insoluble residue, and, as no precipitate
was deposited after standing over night, concentrated to about one
third of its volume. On cooling, this solution threw down a co-
pious precipitate of fine white needles, which were freed from the
benzol mother-liquor by pressing between filter-paper, washed with
dilute potash solution to remove possible traces of benzoic acid, and
the residue taken up in ether. After one or two washings with
water, the ether solution was drawn off, and the residue, after dis-
tilling off the ether, dissolved in ligroine. From this it ciystal-
lized in fine prismatic needles melting at 41-42°. On analysis the
substance gave the following values: —

0.2153 grm. gave 0.5832 grm. CO, and 0.0903 grm. H20.

C6H5CO

Calculated for ^ 0.

Found

CCH0CO

c

74.33

73.87

H

4.43

4.60

The melting point and composition of the body show it to be
without doubt benzoic anhydride, and the study of its properties
confirms this conclusion. It consists of fine, prismatic, needle-like
forms, easily soluble in alcohol, ether, benzol, chloroform and car-
bon disulphide, difficultly in water and in petroleum ether. This

OF ARTS AND SCIENCES. 95

last is the best medium for its crystallization. Cold water con-
verts it slowly, boiling water rapidly, into benzoic acid. Alkalies
transform it into benzoic acid salts, from the solutions of which
mineral acids precipitate benzoic acid in its characteristic leaflets.

The gelatinous phosphoric anhydride residue from the original
benzol solution gave on extraction with benzol only a trace of an-
hydride. As this extract did not appeal to contain any other sub-
stance, the gelatinous residue was taken up in absolute alcohol,
with a view of thus isolating any benzophenone which might have
been formed. As the alcohol was poured upon the residue, con-
siderable heat was manifested. The alcoholic solution was concen-
trated to a small volume, but no crystals could be obtained. After
some days, the alcohol having entirely disappeared, there remained
in the beaker a small quantity of a pleasant-smelling, oily liquid.
This was taken up in water to remove the phosphoric acid, washed
with dilute potash to remove benzoic acid, and extracted with ether.
Finally there remained a few drops of a brownish-colored oil, which,
from its odor, we concluded was benzoic ethyl ester. Unfortunately
the amount was too small and too impure to admit of analysis. Its
formation may be ascribed to the following reaction: —

C6H5CO

) 0 + 2 C2H5OH = 2 C6H5COOC2H5 + H20.
C6H5CO

It is probable that the anhydride necessary for this reaction was
retained, mechanically enclosed, in the gelatinous phosphorous resi-
due, from which it is but incompletely extracted by treatment with
benzol. Phosphoric anhydride being readily soluble in alcohol,
the formation of the ester is easily accounted for. In subsequent
experiments we obtained some more of this oil, which boiled be-
tween 215° and 225°, (benzoic ethyl ester boils at 211-212°,) but
could not get it in sufficiently large quantity to purify for analysis.
The formation of esters of the nitrobenzoic acids, as described
hereafter, under similar conditions, render it practically certain
that the substance we have just described is benzoic ethyl ester.

II. Action of Phosphorpentoxide upon Orthonitrobenzoic Acid
in an Excess of Benzol.

10 grams o-nitrobenzoic acid, melting point 147°, were dissolved
in about 200 c.c. of pure, dry benzol, 10 grams phosphorpentoxide

96 PROCEEDINGS OP THE AMERICAN ACADEMY

added to the hot solution, and the whole hoiled on the steam hath
for ahout three hours. As with benzoic acid, the phosphorpent-
oxide did not dissolve, but settled to the bottom of the flask as
an amorphous, gelatinous mass, which became gradually darker-
colored as the heating progressed, until, at the end of the operation,
it was almost black. The amber-colored, supernatant liquid was
decanted hot through a plaited filter and allowed to crystallize.
After standing over night it had thrown down a considerable
quantity of large, feather-shaped crystals, which, as their amount
did not appear to increase on longer standing, were filtered, and
washed with dry benzol. Their melting point, 147°, and ready
solubility in alkalies, as well as their characteristic sweet taste,
showed them to be the unchanged o-nitrobenzoic acid.

The mother-liquor from these crystals was concentrated to about
one third of its original volume and allowed to stand. The result
was a precipitate of short, thick, prismatic crystals, entirely dif-
ferent from the feather-shaped forms of the nitro acid, and melting
at 128° to 130°. By repeated crystallization from benzol, this
melting point was raised to 133°, at which temperature it remained
constant. The analyses gave the following results : —

0.3393 grm. substance gave 25 c.c. nitrogen at 3.2° and 749.8 mm.
0.2564 grm. substance gave 0.5016 grm. C02 and 0.0700 grm. H20.

Calculated for
p H 1(1) N02

U6"4 \ (2) CO

>

Found.

rw ((2^ CO

C6U4 \ (1) NQ2

c

53.16

53.34

H

2.53

3.03

N

8.86

8.96

In its properties the substance agrees with those assigned to the
anhydride of orthonitrobenzoic acid by Bischoff and Roch,* viz.
difficultly soluble in water and ether, more readily in alcohol, ben-
zol, and glacial acetic acid. Heated quickly upon platinum foil it
explodes. Continued treatment with boiling water or with alka-
lies converts it into the acid. Bischoff and Roch place the melt-
ing point of the anhydride at 135°, while we have not been able to
raise it above 133°.

* Berichte, XVII. 2789.

OF ARTS AND SCIENCES. 97

The phosphoric anhydride residue from which the benzol solu-
tion of o-nitro acid and anhydride had been decanted, yielded only
a small amount of the acid on being extracted with fresh benzol.
As a considerable quantity of insoluble residue still remained
after repeating the operation, we substituted absolute alcohol for
benzol as an extracting agent. With this we obtained a clear so-
lution which was evaporated to dryness, washed with cold water
until free of phosphorus, and recrystallized from alcohol. The
product consisted of small tablets which melted at 30°, and is
in all probability the ethyl ester of orthonitrobenzoic acid. The
amount was too small for an analysis.

III. Action of Phosphorpentoxide upon Meta Nitrobenzoic Acid

in an Excess of Benzol.

10 grams m-nitrobenzoic acid were dissolved in about 200 c.c.
dry benzol, 10 grams of phosphorpentoxide added to the hot solu-
tion, and the whole boiled for three to four hours on the steam bath
under a reverse condenser. As in the previous experiments, the
phosphorpentoxide did not dissolve, but settled to the bottom of
the flask as a thick, gummy mass, which, as the boiling continued,
became rapidly darker-colored.

The supernatant liquid was decanted hot through a plaited filter,
the residue in the flask boiled with fresh benzol, and this extract
added to the first. The solution immediately threw down a pre-
cipitate of fine white needles, which, after drying, showed a melt-
ing point of 161°, which was not raised by recrystallization from
benzol. Dried at 110° the substance analyzed as follows : —

0.3051 grm. gave 0.5871 grm. C02 and 0.0548 grm. H20.
0.2032 grm. gave 0.3904 grm. C02 and 0.0611 grm. H20.
0.2166 grm. gave 0.4160 grm. C02 and 0.0608 grm. H20.
0.3875 grm. gave 28.6 c.c. nitrogen at 6.6° and 748 mm.
0.4021 grm. gave 32.6 c.c. nitrogen at 4.2° and 755.7 mm.

Calculated for

C H \ (l) N°2
UcU* | (3) CO

>0.

Found.

c n 1 (?) CO
^fiU« ) (1) N02

i.

II.

in.

53.16

52.48

52.40

52.37

c

H 2.53 2.00 3.34 3.14

N 8.86 8.82 8.70

VOL. XXVII. (n. S. XIX.) 7

98 PROCEEDINGS OP THE AMERICAN ACADEMY

The complete combustion of the body is an exceedingly difficult
operation. The substance must be thoroughly mixed with the
oxide of copper or lead chromate, and burned very slowly in a
generous current of oxygen. Even under these conditions the
values for carbon are quite low. The chemical relations of the
body, however, leave no doubt that it is the anhydride of meta
nitrobenzoic acid. It dissolves readily in dilute alkalies in the
cold, and from such solution mineral acids precipitate the meta
acid, easily identified by its melting point, 141°, and crystalline
form.

Meta nitrobenzoic anhydride is readily soluble in alcohol, ether,
and chloroform, less readily in benzol (from which solvent it crys-
tallizes best), and difficultly in water. Cold water has but little
effect upon it, boiling water decomposes it rapidly into the free
acid.

From the gelatinous phosphoric residue by extraction with ab-
solute alcohol, evaporating to dryness, and taking up with water,
a product was obtained which crystallized from alcohol in small
rhombic plates, melting at 42°. The same body was obtained by
treating the anhydride with absolute alcohol and phosphorpent-
oxide. Its melting point and method of formation show it to be
the meta nitrobenzoic ester.

IV. Action of Phosplwrpentoxide upon Para Nitrobenzoic Acid

in an Excess of Benzol.

Para nitrobenzoic anhydride is the principal product when para
nitrobenzoic acid and phosphorpentoxide are boiled together for
some hours in an excess of dry benzol. The proportions employed
were the same as with the ortho and meta nitro acids.

The anhydride crystallizes from benzol in white leaflets melting
at 184°. The anakyses gave the following: —

0.1716 grm. substance gave 0.3311 grm. C02 and 0.0530 grm. H20.
0.3461 grm. gave 25.6 c.c. nitrogen at 4.6° and 746.5 mm.

Calculated for

r H J 0) N02
^U* \ (4) CO

>o.

C H f W C0

Found

^U* j (1) N02

c

53.16

52.61

H

2.53

3.40

N

8.86

8.90

OP ARTS AND SCIENCES. 99

Like the isomeric ortho and rneta bodies, the para nitrobenzoic
anhydride is an exceedingly difficult substance to burn. It is but
slightly soluble in alcohol, ether, benzol and carbon disulphide in
the cold, readily however on warming. In ligroine and water it
is insoluble. Continued boiling with water converts it into the
acid. Alkalies produce the same effect, slowly in the cold, more
rapidl}r on heating.

As in the case of the other nitro-anhydrides the phosphoric resi-
due gave, on extraction with absolute alcohol, the para nitrobenzoic
ethyl ester. This may be more readily obtained by boiling the
anhydride with phosphorpentoxide in absolute alcohol solution.

It is proposed to extend the study of this phosphorpentoxide re-
action to other substituted benzoic acids.

100 PROCEEDINGS OF THE AMERICAN ACADEMY

IX.

NOTE ON THE RELATIVE POSITION OF HIGH TEM-
PERATURE MELTING AND BOILING POINTS.

By Carl Barus.

Presented May 24, 1892.

In my work on the measurement of high temperatures,* I largely-
availed myself of boiling points for calibration purposes. With
the aid of suitable apparatus, ebullition can be maintained for an
indefinite length of time, and the boiling point is probably less
influenced by the impurities of the substance. Apart from this,
one of them — the boiling point of zinc — has been so frequently re-
determined by different observers (Becquerel, Deville and Troost,
Violle, and myself) as to have become a veritable landmark in the
region of high temperature, and guaranteed with an accuracy of
about one per cent by actual air thermometry.

Melting points, however, have as a rule been found indirectly,
and those most relied upon to-day are due to the unique calori-
metric work of Violle. I am not aware that anybody has recently
endeavored to compare melting and boiling points with the same
pyrometer, and with especial reference to the boiling point of zinc.
This I have had occasion to do, and the results of the survey made
are unfortunately disappointing.

I made use of a platinum-iridioplatinum thermocouple, which
bad been compared with the porcelain air thermometer between
300° and 1,200°. The couple was thus found to be quite free from
anomalies, and to be quite regular in its thermal variations. It
placed the boiling point of zinc at 930°, or at the lowest estimate
at 925°, agreeing well with the classic results for this datum
referred to.

Now, on using these same couples to determine the melting
points of a number of elements, among which silver, gold, and
copper need here alone be cited, I found that if Zn boils at 925°,

* Bulletin U. S. Geological Survey, No. 54, 1889, Chap. II.

OF ARTS AND SCIENCES. 101

then Ag, Au, and Cu should melt at 985°, 1,093°, and 1,097°,
respectively. Conversely, if Ag, An, and Cu have the Violle
melting points 954°, 1,045°, and 1,054°, respectively, then zinc
should boil at say 895°, or at least 30° below its apparently well
established boiling point.

These difficulties can only be cleared away by minute inquiry
into all the details of experiment involved : for it will be seen that
the- relative positions of these (and other) melting points are well
preserved, and the work already involves variations of method.
The discrepancy increases when higher temperatures are approached
(palladium, nickel, platinum, etc.), and it gradually vanishes on
reaching lower temperatures. In the former case, however, the
limits of the air thermometer are overstepped, and all data are
somewhat hypothetical.

102 PROCEEDINGS OF THE AMERICAN ACADEMY

X.

CONTRIBUTION FROM THE CHEMICAL LABORATORY OF
CLARK UNIVERSITY, WORCESTER, MASS.

ON BIVALENT CABBON.

FIRST PAPER.

By J. U. Nef.

Presented May 11, 1892.

Among the constantly increasing compounds of carbon, there is
but one substance in which the presence of a bivalent carbon atom
is pretty generally accepted, and which is always put forward as
the sole exception to the otherwise constant tetravalence of this
element, namely, carbonic oxide. For a substance possessing two
free affinities,* OO, carbonic oxide is however a remarkably inert
compound, since it absorbs chlorine only very slowly in diffused
light, f and if allowed to stand for weeks in the sunlight with one
molecule of bromine, only a very slow and incomplete reaction
takes placet

Carbonic oxide does not react with iodine or with the haloid
acids. It was found by a special experiment that hydriodic acid
does not react on carbonic oxide at a temperature of 200°, although,
as is well known, this substance adds itself more readily to un-
saturated compounds than any of the other haloid acids.

Carbonic oxide is thus much less reactive than the majority of
the olefine derivatives, many of which form in the cold, and in the
absence of light, addition products with the above named reagents.
This fact depends, as I have already shown in the case of acetacetic
ether, § on the law that an unsaturated compound forms addition

* It is improbable that the two extra affinities in carbonic oxide exist free:
they probably polarize, or mutually saturate each other as in ethylene, so that
it is legitimate to speak of a nascent carbonic oxide.

t Davy, Gilbert's Annalen, XLIII. 296.

\ Emmerling, Ber. d. Chem. Ges., XIII. 873.

§ Ann. Chem. (Liebig), CCLXVI. 52.

OF ARTS AND SCIENCES. 103

products the more readily, the more positive the condition of the
molecule, so that, e. g., ethylene, CH2=CH2, is more reactive than
carbonic oxide, OO, because the presence of oxygen in the latter
substance renders the molecule more negative. For the same
reason, the double bond in sodic acetacetic ether,

CH3 - CONa

II
C02R - CH

is much more reactive than in the ordinary olefine derivatives.

Were it possible now to replace the oxygen in carbonic oxide by
a bivalent radical which is less negative than oxygen, as, for ex-
ample, by (CH3)2, H2, R-N=, H-N=, the resulting compounds,

I II III. IV.

£j§" > C=, H3=0, R-X=C=, HrH>,

would probably be more reactive than carbonic oxide, and perhaps
also than the olefine and acetylene derivatives : the energy of the
compounds must also decrease in the order, I. -IV., given.

All attempts to isolate methylene, H20, or dichlormethylene,
C12=C=, have up to the present time been unsuccessful; especially
have numerous and zealous experiments been carried out in the
hope of isolating the hydrocarbon methylene, H2C= ; as, for in-
stance, attempts to split off water from methylalcohol, CH3OH, by
means of phosphorus pentoxide* or concentrated sulphuric acid,f
or to split off hydrochloric acid from methylchloride by passing
its vapors through red-hot porcelain tubes. $ These experiments
could not however be successful, since the methylene, even if
formed, must again unite with the reagents applied or split off.

A most interesting experiment in this direction was carried out
by Butlerow,§ who found that when methjdene iodide, CH2T2, is
heated in a sealed tube at 100° with copper and water, there is
formed ethylene, CH2 = CH2, and cuprous iodide. This experi-
ment cannot, however, be considered as proving that methylene
is not capable of existence, because already many unsaturated
compounds, especially the acetylene derivatives, show a great ten-
dency to potymerize, and it is therefore highly probable that such

* Dumas, Annales de Chim. et de Phys., LVIII. 128.
t Regnault, Annales de Chim. et de Phys , LXXI. 427.
J Perrot, Ann. Chem. (Liebig), CI. 375.
§ Ann. Chem. (Liebig), CXX. 356.

104 PROCEEDINGS OP THE AMERICAN ACADEMY

an energetic substance as methylene must be expected to be might
polymerize at 100°.

Although methylene or its homologues have not as yet been iso-
lated, there are a number of known substances which possibly may
contain bivalent carbon, as, for instance, prussic acid, HN=0, its
salts, and the so called carbylamines, BrNO, or isonitriles, which
were discovered by Gautier * and Hofmann.f I have therefore
undertaken, in the first place, a very thorough study of these
substances, in order to prove by experiment, if possible, whether
bivalent carbon is present or absent; and in case bivalent carbon
is present, and its properties thus have become more exactly
known, to attempt further the isolation of methylene or of its
homologues ; the latter substances naturally may be expected to be
still more reactive than prussic acid or the carbylamines.

From the experiments which I have the honor to present to the
Academy in this first paper, it will be seen that the presence of
bivalent carbon in the carbylamines, KN=C=, has been proved with
great precision, and, further, it has become very probable that
prussic acid has the formula H-N=C-. The carbylamines are far
more reactive than the ordinary define and acet}rlene derivatives,
but they do not yet equal sodic acetacetic ether in energy of re-
action. Prussic acid, on the other hand, shows, as far as can be
judged now, a reactivity which is not much different from that
shown by the ordinary unsaturated compounds, — facts which are
entirely in accord with the ideas developed above.

The experiments on the isonitriles have been carried out prin-
cipally with phenyl and o-tolylisocyanide. The following addition
products have been obtained thus far, and their constitution proved.
The reactions are given using the general expression BrNO,
where R denotes either

C6H5 or C6H4(CH3 g.

1. Halogens (X2) react at — 15°, with great evolution of heat,

as follows :

R-N=C= + X2 = RN=OX2.

2. Hydrochloric acid reacts with explosive violence at — 15°,
which is avoided, as in case 1, by suitable dilution, and there are
formed addition products of the general formula:

* Annates de Chim. et de Phys., [4.], XVII. 205.
t Ann. Chem. (Liebig), CXLIV. 114, CXLVI. 107.

OP ARTS AND SCIENCES. 105

2EN=C^ , HC1.

3. Phosgene reacts slowly at - 15°, forming quantitatively me-
sox-alkylimidechlorides :

/CI
KNO CI. EN=C(

+ ;co = xco

KK=C= CV EN=C/

XC1

4. Heated for a few minutes at 100°, acetylchloride adds itself
quantitatively as follows :

CI /CI

EN=C= + I = RN=C

CO-CH3 x CO-CH3

5. Benzoylcliloride adds itself slowly at 100° to o-tolylisocy-
anide, and benzoylformic-o-tolyliinidechloride is formed:

CI .CI

CH3-C6H4-NO + I = CH3-C6H4-N=c'

CO-C6H6 XCOC6H5

6. On heating with sulphur at 130°, the isonitriles are converted
quantitatively into the corresponding mustard oils :

RN=C= + S = RN=C=S.

7. Sulphuretted hydrogen reacts at 100°, and forms alkylthio-

formamides :

SH
KNT<> + H2S = KNXT

XH

8. Heated for a short time with primary amines, RNH2, at
180°-220°, the isonitriles are converted into formamidine deriv-
atives :

R-NO + H2NR = KN=(T

XNHR

The isonitriles are converted by means of nascent hydrogen into
secondary amines, RNH-C-H3 : an intermediate product, RN=CH2,
has not as yet been isolated. The isonitriles used were made ac-
cording to Hofmann's method * from primary amines, caustic pot-

* Ann. Chem. (Liebig), CXLIV. 114.

106 PROCEEDINGS OF THE AMERICAN ACADEMY

ash, and chloroform. Hofmann isolated only two products, namely,
phenyl and isoamylisocyanide, the first named substance, as will
be seen later, was not pure nor entirely free from aniline. It was
therefore necessary, in the first place, to find an exact method
for separating isonitriles from primary amines, which was readily
accomplished. It depends simply on the fact that the isonitriles
are not basic substances, so that, for example, an ethereal solution
of aniline and phenylisocyanide can be separated completely by
shaking once with a solution of dilute hydrochloric acid. It fol-
lows, therefore, that the hitherto accepted strong basic property of
the isonitriles is a mistake, and the energy with which these sub-
stances unite with haloid acids depends, not on their basic nature,
but on the presence of bivalent carbon.

Gautier,* to whom unquestionably belongs the priority in the
discovery of the isonitriles, introduced the name carbylamines for
them because of their supposed strong basic properties. He re-
garded them as ammonia in which one hydrogen atom was replaced

by alkyl, while the other two were replaced by C", ™, - NIIT, and

supposed them to react with the haloid acids like ammonia, going

"P "j
over thus from trivalent into pentavalent nitrogen, „,, [- Nv, HX.

This was the chief reason that led him to disregard the other

possible formula, ^1V -] Nv, for the isonitriles.

In a similar manner Gautier t regarded the alkyl-cyanides (am-
monia, in which the three hydrogen atoms are replaced by trivalent
KrC-) as weak bases, because they unite with gaseous hydrochloric

* Annales de Chim. et de Phys., [4.], XVII. 205. I cite here exclusively
from Gautier's paper in Annales de Chimie et de Physique, [4.], XVII. 103-260
(1869), which includes the following previous papers:

Ann. Chem. (Liebig), 138.38 142.294 145.118 146.119,352 149.29,155 151.239 152.221
Bull, de la Soc Chim., 4.88 11.214 11.222

Comptes Rendus, 63.920 65.410 It'lel"72 67 713*804

In this paper Gautier describes the compounds more fully, and corrects a
number of his previous statements. The statements of Gautier on prussic acid,
the nitriles and carbylamines in Beilstein, and other treatises on organic chem-
istry, are therefore incomplete, since remarkably enough this last paper has not
been taken into consideration. I regret that the These of Gautier (Paris, 1869),
which may possibly contain still more details, has not been accessible to me.

t Ibid., pp. Ill, 118.

OP ARTS AND SCIENCES. 107

and hydrobromic acid. We know now, because of the experiments
of Michael and Wing,* that the resulting compounds are not salts,
hut addition products : acetonitrile, for example, forms with hydro-
chloric acid

CH3-ONH
\
CI

It is now pretty generally conceded, especially also because of
Wallach's f experiments, that hydrochloric acid forms with alkyl-
cyanides either amide or imidechlorides,

^NH2 /NH

R-(T or R-Cf

XC12 XC1

Gautier t has brought forward as a further proof for his carbyl-
amine formula the fact that methyl and ethyl cyanate are formed by
the oxidation of methyl and ethyl isocyanide respectively. These
oxidation products, however, are formed as side products, the chief
products being very complicated compounds, as C7H12lSr204 and
C8H12N405 (from CH3NC), and C9H22N4Oa as well as Cl3H25N"504
(from C2H5NC).

It seems to me, therefore, that this reaction cannot be regarded
as sufficient to decide the constitution of the isonitriles, since it is
likely that a substance having the constitution RNV=CIV may also
give alkylcyanate, R]ST=C=0, by oxidation.

The chief argument of Gautier for his carbylamine formula,

p„ -] Nm, namely, the supposed strong basic properties of the com-
pounds, has already been proved untenable. Furthermore, the pres-
ent views with regard to the nature of the isonitriles differ; whereas
some chemists § consider the presence of bivalent carbon as possi-
ble; others, as Hofmann,|| V. Meyer and Jacobson,1[ v. Richter,**
favor the formula R-^C, while Beilstein ff simply writes RNC.
The above briefly stated facts, which are given in detail in the

* Amer. Chera. Journal, VII. 72.

t Ann. Chem. (Liebig), CLXXXIV. 1, CCXIV. 192

t Loc. at., XVII. 228, 242, 255.

§ Graham Otto, Lehrbuch der org. Chemie, neue Ausgabe von Kolbe und
E. v. Meyer.

|| Ber. d. chera. Ges., X. 1095.
IT Lehrbuch der org. Chemie, I. 252.
** Ibid., translation by E. F. Smith, p. 287.
tt Handbuch der org. Chemie, I. 1173, Zweite Aufl.

108 PROCEEDINGS OP THE AMERICAN ACADEMY

following experimental portion, are sufficient to furnish the com-
plete proof that the isonitriles possess the constitution represented
by the formula E.NO: furthermore, the name carhylamine is no
longer justifiable for this class of compounds, because the members
are not bases, as this name represents.

Experimental Part.

I. On Phenylisocyanide, C6H5N=C=.

Preparation of Phenylisocyanide. — To a solution of 240 grams
caustic potash in 800 c.c. alcohol (99%) is added slowly, by means
of a drop funnel, a solution of 100 grams aniline in 214 grams chlo-
roform. Eeaction sets in at first with great violence, so that the
solution soon reaches its boiling point. It is therefore necessary
to cool continually, and the temperature is best kept at about 50°,
because, if cooled too much, reaction sets in all at once, and with
violence. After standing for a short time, during which complete
reaction slowly takes place, and much potassic chloride has sepa-
rated out, the alcohol is distilled off* on a water bath, and a litre
of hot water poured over the residue, in order to dissolve the potas-
sic chloride. On cooling, the upper oily layer, consisting of ani-
line and phenylisocyanide, is drawn off, and the aqueous solution
extracted with ether. The ethereal solution is washed with 120
grams hydrochloric acid (sp. gr. 1.15), previously diluted to a litre;
this is best done in two portions, using three fourths at first, and
then the remainder. By this treatment all the unchanged aniline,
as well as some diphenylformamidine formed, go into the acid so-
lution, while the phenylisocyanide remains dissolved in the ether.
The ether is distilled off without first drying it, and the dark brown
colored residue distilled with steam. Phenylisocyanide is carried
over very quickly as a colorless oil, which on standing soon be-
comes colored pale green. It is again extracted with ether after
adding a small amount of dilute sulphuric acid, and the ethereal
solution dried with caustic potash, and, after getting rid of the
ether, the dark blue residual oil is distilled under reduced pres-
sure. Phenylisocyanide boils at 64° at 20 mm., at 71° at 30 mm.,
at 78° at 40 mm. pressure, leaving a slight blue residue (poly-
meric product).

* Small amounts of aniline and isonitrile are carried over with the alcohol,
which, however, it is not worth while to work up. It is not possible to use the
alcohol over again, since it contains chloroform.

OF ARTS AND SCIENCES. 109

The distillate, as above with steam, is at first perfectly colorless,
but becomes light blue in a few minutes, and in an hour is changed
to a deep dark blue liquid, which gets darker and darker; in the
course of a few weeks it becomes viscous, and at the same time
purple red needles begin to appear. After three months standing,
the whole mass is changed to a solid resin, which, brought on clay-
plates and pulverized, goes over into a brown powder. This is
probably a polymeric product, and from the above it is evident
that phenylisocyanide is an extremely unstable substance. For all
the reactions mentioned in this paper freshly distilled phenylisocy-
anide must therefore be used. At higher temperatures, already
at 100°, polymerization takes place very quickly. At ordinary
pressure phenylisocyanide boils at 165°-166°, and although at first
a small portion goes over colorless, much polymerization takes place.

Hofmann's product evidently contained some aniline, since he
says * that on distillation it is converted into an odorless substance
crystallizing in needles and partly volatilizing at 230°. The latter
substance was in all probability diphenylformamidine formed by
the action of the aniline present on phenylisocyanide (see below).
Weith f obtained the same substance on heating phenylisocyanide
in sealed tubes at 220°.

The isonitriles $ all burn with very great difficulty, § because of
the formation of polymeric products, and it was possible to obtain
good analytical results only by mixing with lead chromate. The
nitrogen determinations also come low, unless the substance is
mixed with copper oxide, and heated long and very hard (see
analyses I. and II.).

0.1145 gram substance gave 0.3411 gram C02 and 0.0554 gram

H20.
0.1452 gram substance gave 16.2 c.c. moist nitrogen at 18° and

757 mm.
0.1803 gram substance gave 22 c.c. moist nitrogen at 20° and

754 mm.

* Ann. Chem. (Liebig), CXLIV. 118.

t Ber. d. chem. Ges., VI. 213.

f Hofmann, Ann. Chem. (Liebig), CXLIV. 117, has analyzed phenylisocy-
anide, but he gives no analytical data.

§ It is therefore possible that azulmic acid, which is formed by the polym-
erization of prussic acid, is free from oxygen, especially since no concordant
results have been obtained in its analysis by different chemists. Cf. Gautier,
loc. at., XVII. 158 and 161.

110 PROCEEDINGS OF THE AMERICAN ACADEMY

Found.

II.

c

Theory for
C7H5N.

81.55

i.
81.25

H

N

4.85
13.60

5 37

12.84

13.84

Phenylisocyanide is lighter than water, specific gravity 0.977 at
15° (Westphal). It possesses a horrible smell, a bitter taste, and
causes headaches and flow of the saliva. Continued inhalation of
its vapors produces nausea, and nervous exhaustion.*

Nascent hydrogen converts it into mononiethylaniline : 10 grams
were dissolved in 90 grams amylalcohol, 6 grams of sodium added,
and the mixture heated to boiling until the sodium had disap-
peared. The smell of isocyanide was no longer present, and after
washing the amylalcohol with water it was treated with dilute
hydrochloric acid, and the acid solution evaporated one half on a
water bath, and then made alkaline : the oil which separates out was
extracted with ether, and dried with anhydrous sulphate of copper.
On fractional distillation, 7 c.c. of an oil, boiling from 187°-
191°, were obtained, which treated in acid solution with sodic
nitrite gave the well known methylaniline nitroseamine. This
was converted back again by means of tin and hydrochloric acid
into mononiethylaniline (bpt. 189°-192°); the latter substance
finally treated with acetic anhydride, and thus 4 grams of methyl-
acetanilide (mpt. 99°) were obtained. These reactions were so
conclusive that an analysis of the mononiethylaniline was consid-
ered superfluous.

Gautierf has shown that methyl- and ethyl-isocyanide react with
acetic acid as follows :

,COCH3

HOCOCH, -o^t_^ H ^/

CO-CH3

EiW + H6COCH3 = EN=COH + °n

Alkyl Formamide.

Phenylisocyanide reacts with acetic acid (2 molecules) slowly at
ordinary temperature, forming acetic anhydride and formanilide,

C6H5N=Cqtt

* Gautier states, loc. cit., XVII. 218, that methyl and ethylisocyanicle are
not really to be regarded as poisonous substances, since several drops of either
when put in the eyes or mouth of a dog had absolutely no effect, and even
0.5 gram put on an open wound produced no apparent effect. He states, how-
ever, that they have a marked effect on the human system.

t Loc. cit., XVII. 223 and 241.

OP ARTS AND SCIENCES. Ill

which can he easily separated by fractional distillation under re-
duced pressure : the former suhstance was then identified by its
hoiling point (137°), hut the formanilide obtained is never pure,
hut contains a considerable quantity of acetanilide from which it
can he separated by recrystallization from ligroine and benzene.
This is due to the fact that formanilide, as shown by a special
experiment, is converted almost entirely in half an hour at 90° by
acetic anhydride into acetanilide.

A new experiment was therefore tried, using formic acid instead
of acetic acid, in the hope of obtaining thereby formic anhydride
which has not yet been isolated.

On mixing phenylisocyanide with pure formic acid (mpt. 8°. 6)
at 0°, a very violent reaction takes place, with much evolution of
gas : the phenylisocyanide was therefore slowly poured into well
cooled formic acid (2 molecules), whereby immediately at 0° a
steady evolution of pure carbonic oxide takes place. On distilling
the residue, only formanilide was obtained, which boils at 283°-
285° almost without decomposition, and, recrystallized from ligro-
ine, melts at 48°. The product obtained is identical in every re-
spect with a formanilide made according to the method of Wallach
and Wiisten.* This experiment shows that formic anhydride,
which probably is formed as an intermediate product,

H
CO

H
C6H5-N-C= + ggSo = C°H^=COH + °(co

H

H

is not capable of existence at 0°, but decomposes spontaneously
into 2 CO and H20. Gerhardt f has already attempted, without
success, to obtain this substance from benzoylchloride and sodic
formiate. The following further observation was then made in
this direction. On pouring phosphorus oxychloride (1 molecule)
over potassic formiate (4 molecules), a violent reaction takes place
at 0°, and much carbonic oxide is evolved.

On adding anhydrous oxalic acid to phenylisocyanide, reaction
takes place at 0° and formanilide, carbonic oxide, and carbon diox-
ide are formed, which makes it likely that oxalic anh}Tdride, proba-
bly formed as an intermediate product, decomposes spontaneously.

* Ber. d. chem. Ges., XVI. 145.

t Ann. Chem. (Liebig), LXXXVII. 149.

112 PROCEEDINGS OF THE AMERICAN ACADEMY

On heating phenylisocyanide for six hours in a sealed tube at
130° with an alcoholic solution of sodium ethylate (1 molecule),
there is formed in large quantity diphenylformamidine * (mpt.
138°). The formation of this substance is explained most simply
by assuming that in the presence of sodium ethylate alcohol adds
itself to the phenylisocyanide, forming phenylformimidoether,

/OC2H5

c6h5n=c;

That such substances go over into diphenylformamidine,

.NHCVEL;
C6H5N=C(

with remarkable ease is evident from the work of Comstock and
Kleeberg; f and Pinner J also has shown how easily formimidoether,

HN=c'
XH

OC2H5

goes over into formamidine,

HN=C

NH2

XH

Experiments undertaken with the object of adding sodium ethyl-
ate or methylate to phenyl- or o-tolylisocyanide have so far been
unsuccessful, because on heating in sealed tubes at 130°, much
polymerization takes place. Such an addition would be especially

interesting, because carbonic oxide, 0=C^, according to Berthelot,§

directly adds caustic potash,

OC= + KOH = OC^-K

and, according to Geuther and Frohlich,|| also sodium methylate

and ethylate,

.ONa
OC= + NaOB = OCT

XR

* Hofmann, Jahresber. 1858, p. 854.
t Amer. Chem. Journal, XII. 498.
t Ber. d. chem. Ges., XVI. 354 and 1644.
§ Ann. Chem. (Liebig), XCVII. 125.
|| Ann. Chem. (Liebig), CCII. 290.

OP ARTS AND SCIENCES. 113

Gautier * noticed that niethylisocyanide reacts with methyl-
iodide, and forms, hesides much resinous matter, a product soluble
in water. That in this case no addition product,

/I
CH,N=CT

XCH3

has been formed, but that polymerization has taken place, follows
from the work of Ljubjawin,f who studied this reaction more
closely. It follows further from the investigations of Wallach, t
that a substance of the above nature must be very unstable, if in-
deed capable of existence ; and that it would probably lose hydrio-
dic acid and go over into basic products. I found, as did Ljubjawin
in the case of ethylisocyanide, that on heating phenylisocyanide
with ethyliodide at 100° exclusively polymerization takes place.
That phenylisocyanide reacts with hydrogen sulphide, forming

thioformanilide,

.SH
C6H5N<T

XH

has been shown by Hofmann § ; that it reacts with sulphur to form
phenylmustard oil, C6H5N=OS, has been made probable by the
experiments of Weith,|| who obtained sulphocarbanilide on heating
phenylisocyanide containing aniline with sulphur. Weith H has
also shown that on heating aniline and phenylisocyanide in sealed
tubes at 220°, diphenylformamidine

NHC6H5
C6H6N=c'

XH

is formed. I can confirm his experiments, and obtained 30% yield
in this case.

On pouring phenylisocyanide over dry silver oxide, or mercuric
oxide, an extremely energetic reaction takes place : an ethereal
solution of the isonitrile, with one molecule of mercuric oxide,
heated to about 60° in a sealed tube, exploded with great violence.
On heating the same mixture gently on a water bath with reversed

* Loc. cit, XVII. 226.

t Ber. d. chem. Ges., XVIII. R. 407.

\ Ann. Chem. (Liebig), CLXXXIV. 86 and 108, CCXIV. 221.

§ Ber. d. chem Ges., X. 1095.

|| Ibid., VI. 210. f Ibid., IX. 454.

VOL. XXVII. (n. S. XIX.) 8

114 PROCEEDINGS OP THE AMERICAN ACADEMY

condenser, reduction of the mercuric oxide is noticed at 40°, and
also the characteristic smell of phenylcyanate ohserved. The
quantity of this substance formed was very small, and a large
amount of gaseous products appear, so that it would necessitate
the sacrifice of too much material in order to obtain sufficient phe-
nylcyanate for an analysis. The experiments were therefore not
continued, especially as Gautier* has already accomplished this in
the case of methylisocyanide.

Isocyanphenylchloride, or Phenylimidocarbonylchloride,

C6H5N = OCl2.

On passing dry chlorine iuto a well cooled solution of phenyliso-
cyanide in five to six times its volume of chloroform, the gas is
absorbed instantly and completely, without the slightest trace of
hydrochloric acid being formed. The reaction is complete when
the color of the solution changes suddenly from blue to yellow.
The chloroform solution is washed immediately with dilute sodic
hydrate, dried with calcic chloride, and then fractionated. A
colorless oil is obtained boiling at 204°-205° (uncorr.), or at 209°-
210° (thermometer entirely in the vapor).

0.2740 gram substance gave 0.4822 gram C02 and 0.0755 gram

H20.
0.0779 gram substance gave 0.1298 gram AgCl on ignition with

CaO.

Theory for C7H5NC12. Found.

C 48.27 47.99

H 2.88 3.06

CI 40.80 41.22

Isocyanphenylchloride is a colorless, sharp-smelling oil, which
attacks the eyes strongly. On heating it with acetic acid, acet-
anilide is formed; with water, s. diphenylurea; with silver oxide,
phenylcyanate; with alcohol, phenylurethane. On heating it with
aniline, all at once a very violent reaction takes place, which can
only be regulated by taking small quantities (about 2 grams).
There is left a white mass, the hydrochloride of a base, which
crystallizes from dilute alcohol in colorless scales, melting at 241°.
On addition of ammonia to an aqueous solution of the salt, the free
base separates out. After being twice recrystallized from alcohol,

* Loc. cit., XVII. 229.

OP ARTS AND SCIENCES. 115

it showed the melting point 143°, and was identical in every re-
spect with the long known a-triphenylguanidine,*

.NHC6H5
C6H5N=(T

XNHC6H5

Hence the constitution of the dichloride, C6H5N = OCl2, is proved.
An analysis of the guanidine derivative gave the following result :

0.1981 gram substance, dried at 105°, gave 0.5770 gram C02 and
0.1121 gram H20.

Theory for Ci9H]7Ns. Found.

C 79.44 79.43

H 5.93 6.28

The above mentioned reactions and properties of isocyanphenyl-
chloride show in many respects coincidence with an isocyanphenyl-
chloride, which Sell and Zierold t have obtained from phenylmus-
tard oil and chlorine; only as regards boiling point and behavior
towards aniline is there a difference. Sell and Zierold give the
boiling point 211°-212°, and state that the oil is yellow; they
obtained further on treatment with aniline, besides much resinous
matter, the hydrochloride of an isomeric triphenylguanidine, which
melts at 207°, and contains half a molecule of crystal water. They
state that a carbon and hydrogen, as well as nitrogen determina-
tion of the salt gave figures t agreeing exactly for a base,

.NHC6HS
C6H5N=C(

XNHC6H5

They did not succeed in isolating the free base, as rapid resin
formation was noticed in attempts to set it free. I have succeeded
in clearing up these differences : the product described by Sell and
Zierold as isocyanphenylchloride was a mixture of isocyanphenyl-
chloride and chlorinated isocyanphenylchlorides, C1-C6H4-N=CC12.
A number of observations given in the paper of the chemists named
point towards this: they obtained, e. g., on treating the crude
product with ammonia, a substance which they consider to be

* Merz and Weith, Zeitschr. fiir Cliemie, 1868, p. 513.
t Ber. d. chem. Ges., VII. 1228.

| Sell and Zierold give no analytical data, nor do they state with what salt,
whether C19H17N, 2 HC1, or C19Hl7N, HC1, the analyses agree.

116 PROCEEDINGS OP THE AMERICAN ACADEMY

C1C,H4N=C '

NH2

because on treatment with caustic potash it is converted into
chloraniline.

The product described as isotriphenylguanidine hydrochloride
(mpt. 207°) was either the salt of a chlorinated triphenylguani-
dine, or perhaps still a mixture.

Sell and Zierold state that on passing chlorine gas into phenyl-
mustard oil no substitution takes place; it follows that probably,
on fractionating the products of the reaction, C6H5N = CC12 + SC12,
chlorine is set free,* and then substitution takes place. That this
is so is proved by the following experiment, which leads to pure
isocyanphenyl chloride. 100 grams of phenyl mustard oil were
treated according to the directions given by Sell and Zierold with
chlorine, and, as soon as no more absorption of the gas is noticed,
the chloroform solution is poured slowly, with thorough shaking,
into much water, in order to decompose the SC12 formed. The
chloroform solution, after treating with sodic hydrate, is dried with
calcic chloride, and on fractional distillation a colorless oil ob-
tained boiling at 204°-205° (80 grains), which is identical in
every particular with the product obtained from phenylisocyanide
and chlorine. On treatment with aniline it is converted into tri-
phenylguanidine hydrochloride (mpt. 241°). The free base ob-
tained therefrom melts at 143°, and a nitrogen determination gave
the following result : —

0.2142 gram substance, dried at 105°, gave 27.5 c.c. moist nitrogen
at 19°, and 748 mm.

Theory for C19H17N3. Found.

N 14.63 14.52

An analysis of the isocyanphenylchloride obtained from phenyl-
mustard oil and chlorine gave the following results : —

0.1542 gram substance gave 0.2725 gram C02 and 0.0431 gram

H20.
0.3003 gram substance gave 21.1 c.c. moist nitrogen at 20° and

756 mm.
0.1052 gram substance gave 1754 gram AgCl on ignition with

CaO.

* SC12 is decomposed by distillation, as is well known, into S2C12 and Cl2.

OF ARTS AND SCIENCES. 117

Theory for C^NCl*.

Found.

c

48.27

48.19

H

2.88

3.15

N

8.05 k

7.99

CI

40.80

41.24

On treating phenylisocyanide in chloroform solution with one
molecule of bromine at 0°, absorption takes place instantly with-
out a trace of hydrobromic acid being formed; after distilling off
the chloroform, a yellow oil, probably C6H5]S"=CBr2, remains, which
could not be distilled in vacuum, nor be otherwise purified.* On
adding to a solution of phenylisocyanide in carbon bisulphide, a
carbon bisulphide solution of iodine (1 molecule), immediate de-
colorization of the iodine is noticed, as well as a marked evolution
of heat, and a dark yellow oil, probably the iodide, C6H5N=CI2,
obtained.

C6H5N=C(
Mesoxanilid-imidechloride, CO

C6H6N</

XC1

To 5c.c. phenylisocyanide, cooled to —20°, are added 5c.c. of
phosgene t (cooled to —20°), and the mixture protected by calcic
chloride tubes from moist air. After standing for an hour at —20°,
the mixture is taken out of the freezing solution until the temper-
ature has risen to about 0°, and then cooled again, etc., until no
spontaneous evolution of heat is noticed. The experiment cannot
well be carried out with larger quantities than given above : 16 cc,
e. g., of a mixture in a tube cooled with ice and salt reacted all at
Once, while attempting to seal it up, so energetically that balf the
mixture was thrown out of the tube.

Several portions treated as above mentioned were therefore united,
and the excess of phosgene removed by heating on a water
bath, and the residual oil, which contains no trace of isonitrile,
fractionated under diminished pressure. A viscous hygroscopic
j-ellow oil is obtained, having an acid and at the same time an
agreeable smell, which boils with slight decomposition at 145°-
152° at 15-20 mm. pressure.

* Tscherniak, Bull, de la Soc. Chim., XXX. 185, obtained in a similar man-
ner, by treating methylisocyanide with bromine, a yellow unstable oil, which
could not be purified, and which he did not study further.

t The same result is obtained on pouring the isonitrile into the phosgene.

118 PROCEEDINGS OP THE AMERICAN ACADEMY

0.2490 gram substance gave 0.5216 gram C02 and 0.0721 gram

H20.
0.3001 gram substance gave 22 c.c. moist nitrogen at 17° and

760 mm.
0.1789 gram substance gave 0.1857 gram AgCl (Carius).

Theory for C15H10N2Cl2O.

Found.

c

59.01

57.13

H

3.29

3.22

N

9.18

8.51

CI

23.12

25.68

Although the above analytical figures do not agree exactly with
the theoretical ones, it is highly probable that the substance is
mesoxanilidiinidechloride, especially because of the almost quanti-
tative conversion into mesoxanilide (mentioned below). It is most
likely that the oil still contained traces of phosgene, since it was
distilled only once. Furthermore, Wallach in his well known re-
searches on imide and amidechlorides * very seldom obtained good
analytical results, because of the instability of these compounds,
even when the substances were obtained in the crystalline form.

Mesoxanilidimidechloride has thus been formed quantitatively
according to the following equation:

C6H5N=C= CI . C6H5N=C '

+ XCO = CO

C6H5N=C= Clx C6H6N=C

XC1

That in this case not a trace of oxanilchloride imidechloride is
formed, according to the equation

C6H5K=C= + COCl2 = C6H5N=CT

x CO-C1

is shown below under mesoxanilide.

* Ann. Chem. (Liebig), CLXXXIV. 9.

OF ARTS AND SCIENCES. 119

Mesoxanilide and its Derivatives.

Mesoxanilid-alcoholate = Monoethylether of Dloxymalonic Anilide,

C6H5N=CXc,OH
CeH^C7 0C2Hs

Mesoxanilidimidecliloricle takes up water slowly from the air
and becomes solid. On pouring a large amount of water over the
oil, and stirring with a glass rod, all at once reaction sets in, with
marked evolution of heat, and the mass solidifies; in order to de-
compose mechanically enclosed material, it is converted by means of
a pestle into a fine powder. The grayish white residue consists of
almost pure mesoxanilidehydrate, and equals in weight the phenyl-
isocyanide taken in the first place. It was generally made directly
from the crude, not distilled mesoxanilidimidechloride. In order
to purify this, it was recrystallized twice from boiling alcohol,
which converts the hydrate into the alcoholate.

0.1686 gram substance dried over H2S04 in vacuum gave 0.4077

gram C02 and 0.0896 gram H20.
0.2074 gram substance gave 16.7 c.c. moist nitrogen at 16° and

742 mm.

Theory for C17H]8N204. Found.

C 64.97 65.94

H 5.73 5.90

N 8.92 9.11

Mesoxanilid-alcoholate is readily soluble in hot, but only slightly
so in cold alcohol, and crystallizes out in colorless silky needles.
On heating it in a capillary tube it begins to get yellow at 100°,
and melts with gas evolution (alcohol) at 145° to 151°, according as
the temperature is raised slowly or quickly. In boiling alcoholic
or benzine solution, the alcoholate dissociates to a marked extent,
and the solutions are colored pure yellow, but on cooling, already
at 50° they become colorless. This explains why in the above
analysis the per cent of carbon found was somewhat high. The
alcoholate dissolves in dilute sodic hydrate and slightly in hot
water whereby, however, it is converted into mesoxanilidehydrate.

120 PROCEEDINGS OF THE AMERICAN ACADEMY

C6H5N=C°H

Mesoxanilide, . CO.

C6H5N=C

OH

This substance is formed by long heating of mesoxanilidehydrate,
or alcoholate, first at 100°, then at 108°-116°, whereby the alcohol
or the water respectively goes off very slowly as is seen by the fol-
lowing figures : —

0.9470 gram alcoholate lost, after heating 3| hours at 100°, 0.0634

gram.
0.9470 gram alcoholate lost, after heating 4 hours at 108°-113°,

0.1240 gram.
0.9470 gram alcoholate lost, after heating 3 hours at 113°-115°,

0.1322 gram.
0.9470 gram alcoholate lost, after heating 3 hours at 116°, 0.1350

gram.
0.9470 gram alcoholate lost, after heating 2\ hours at 109°, 0.1352

gram.

Heated altogether 16 hours, until constant weight was obtained.

Theory for Loss of 1 Molecule Alcohol. Found.

14.65 14.28

The analysis of the yellow powder thus obtained gave the fol-
lowing results : —

0.1546 gram substance gave 0.3841 gram C02 and 0.0661 gram H20.
0.2086 gram substance gave 19.5 c.c. moist nitrogen at 17° and
743 mm.

Theory for C15H12N203. Found.

C 67.28 67.75

H 4.48 4.75

N 10.45 10.60

Mesoxanilide is soluble without change only in such solvents
as contain no alcohol or water; on pouring water or alcohol
over it and warming gently, it becomes colorless, forming tbe
alcoholate or the hydrate. The substance, in fact, shows a great
resemblance to chloral, which also contains a very reactive carbonyl
group.

On treating an anhydrous benzine solution of mesoxanilide with
phenylhydrazine, it becomes colorless at first, and then a volumi-

OF ARTS AND SCIENCES. 121

nous white precipitate separates out, which, heated to 100°, goes
over with loss of water into mesoxanilide-phenylhydrazone de-
scribed below. In this case, therefore, a simple addition of phenyl-
hydrazine to the carbonyl group takes place,

C6H5N=C°H C6H5N=C°H /OH

;co + h2n-nh-c6h5 = ;c(

C6H6N=C ' CeH^c' X NHNHC6H5

analogous to the action of ammonia on chloral.* On heating
mesoxanilide with acetic anhydride reaction takes place just as in
case of chloral, f and a colorless substance crystallizing in needles,
and melting at 190° is formed: —

C6H5N=CN
Mesoxanilide-phenylhydrazone, yC = N-NHC6H5.

OH
V

/

C6H6N=Cq

On adding to a warm alcoholic solution of mesoxanilid-alcoholate
one molecule of phenylhydrazine, there is formed almost immedi-
ately a voluminous white precipitate, which, filtered off and put on
clay plates, is converted into a white powder. This is the hydra-
zone alcoholate,

C6H5N=C°H.OC2H5

c

C6H5^C^H X NHNHC6H5 ;

so that the reaction between the two substances taken has simply
been a splitting off of one molecule of water. In order to convert
the substance obtained into the hydrazone, it was heated at 115°
to constant weight, which is attained after 10 hours.

0.1526 gram substance gave 0.3937 gram C02 and 0.0729 gram

H20.
0.1532 gram substance gave 20.5 c.c. moist nitrogen at 16° and

745 mm.

Theory for C21H18N402. Found.

c

70.39

70.36

H

5.03

5.31

N

15.64

15.29

* Stadeler, Ann. Chem. (Liebig), CVI. 253.

t V. Meyer and Dulk, Ann. Chem. (Liebig), CLXXI. 73.

122 PROCEEDINGS OP THE AMERICAN ACADEMY

The hydrazone, which is a yellow powder as ohtained above, melts
with decomposition at 163°; it dissolves rather easily in acetic
acid, acetone, and benzine, but very slightly in alcohol and ether.
It is insoluble in alkalies, and crystallizes from acetic acid in
yellow leaflets. It does not take up water or alcohol again, which
shows that in the above described hydrate and alcoholate these
could not have been present in the form of crystal water.

Mesoxanilidehydrate = Dloxymalonic Anilide,
C6H5N<\cOH

The crude mesoxanilidehydrate, which is directly obtained from
mesoxanilidimidechloride and water, is best purified by dissolv-
ing in warm dilute sodic hydrate, reprecipitating with hydro-
chloric acid, and recrystallizing from water. It dissolves in
boiling water in very slight amount (about one gram in a litre),
and on cooling comes out in colorless needles, which do not change
in weight on long standing over H2S04 in vacuum. The crude
hydrate can also be purified by recrystallization from warm (50°)
alcohol; but in this case there is danger of a partial conversion
into the alcoholate (see analysis I.). The pure alcoholate can,
however, be completely converted back into the hydrate by dis-
solving it in sodic hydroxide, precipitating with acids, and recrys-
tallizing from water (see analysis II.).

I. 0.1683 gram substance, recrystallized from alcohol (50°), and
dried over H2S04 in vacuum, gave 0.3961 gram C02 and
0.0753 gram H20.
II. 0.1565 gram substance, obtained from the alcoholate as above
mentioned, gave 0.3604 gram C02 and 0.0711 gram H20.
0.2508 gram substance gave 21.2 c.c. moist nitrogen at 17°
and 763 mm.

Theory for Found.

C1EH,4N204. I. II.

C 62.93 64.18 62.81

H 4.89 4.97 5.05

N 9.79 9.85

Mesoxanilidehydrate is soluble in benzine and acetic ether; the
hot solutions are colored yellow, but in cooling become colorless,

OP ARTS AND SCIENCES. 123

which shows that dissociation takes place on warming. On add-
ing phenylhydrazine to a lukewarm solution of the hydrate in ben-
zine, the hydrazon-hydrate already mentioned above separates out
in white rlakes. Mesoxanilidehydrate, heated in a capillary tube,
behaves just like the corresponding alcoholate (see p. 119); heated
at 100°, it loses one molecule of water very slowly, going over into
yellow mcsoxanilide. It requires about fifteen hours' heating at
100°-110°.

The most remarkable property of this substance is, however, its
acid nature; it reddens blue litmus in aqueous solution, and dis-
solves without change in dilute sodic hydrate and carbonate.

The fact that a substance containing the carbonyl group can
attain acid properties by taking up one molecule of water,

pOH
/OH

as well as the proof that phenylhydrazine simply adds itself in the
first stage to a carbonyl group,

C6H6NHNH

c6h5nhnh2 + oc; = ;cr

x HOx x

I regard as the most important result of the work on mesoxani-
lide. They will be fully discussed in connection with other ob-
servations at the end of this paper. I would like, however, to
make here a few remarks concerning the constitution of the acid
amides. It seems to me that the interesting experiments of Tafel
and Enoch, in the case of benzamide,* and of Comstock and Klee-
berg,f in the case of formanilide, have made it very probable that
the acid amides possess the constitution represented by the formula

.OH
EC'

^NH

It follows that the product obtained by the action of ammonia on

an acid ether,

.0

E-C^

NOE

* Ber. d. chem. Ges., XXIII. 103 and 1550.
t American Chem. Journal, XII. 493.

124 PROCEEDINGS OF THE AMERICAN ACADEMY

namely,

must take up water,

XM2

OH
'OH

R-cr

XNH2

and then again split off water in a different way,

/OH

so that this reaction is not as simple as was formerly supposed.

The different behavior of the silver and sodium salt of an acid-
amide seems to me to be cleared up by the work on acetacetic
ether,* without the very improbable assumption that the salts are
differently constituted, i. e. that tautomerism exists in this class
of compounds.

Mesoxalic-acid-phenylhydrazone, from Mesoxanilidehydrate.

The proof that the above compounds are in reality derivatives of
mesoxalic acid is the following.

Mesoxanilidehydrate was dissolved in four molecules pure sodic
hydrate, and evaporated to dryness on a water bath. After taking
up with water, and extracting with ether (to get rid of aniline
split off), the aqueous solution was heated for 1£ hours longer, and
then again evaporated to dryness, f After acidifying with dilute
hydrochloric acid, whereby an evolution of carbon dioxide is no-
ticed, and adding phenylhydrazine hydrochloride, a voluminous
yellow precipitate results. It was purified by dissolving in dilute

* Ann. Chem. (Liebig), CCLXVT. 135.

t It is necessary to heat so long because mesoxanilidehydrate goes over
into mesoxalic acid with difficulty. In the first experiment the alkaline solu-
tion was evaporated only once on a water bath. On acidifying, and adding
phenylhydrazine hydrochloride, a substance separated out in yellow needles,
which, recrystallized from alcohol, melted with decomposition at 153°.

The analysis gave results agreeing well with an intermediate product,

C6H5N=C°H

^C=NNHC6H6:

HOCO

Theory.

Found.

c

63.60

63.17

H

4.59

4.62

OF ARTS AND SCIENCES. 125

soda, acidifying, and washing the resulting yellow precipitate
thoroughly.

0.1571 gram substance gave 0.2986 gram C02 and 0.0577 gram H20.

Theory for C9H8N204.

Found.

c

51.92

51.83

H

3.85

4.08

The substance melts between 158°-164° with decomposition, and
is identical in every respect with a phenylhydrazone of mesoxalic
acid, which Elbers first obtained from mesoxalic acid and phenyl-
hydrazine, and which has since been obtained in other ways by
R. Meyer* and v. Pechmann.f

That not a trace of oxanilchloride imidechloride,

x CO-C1

is formed by the action of phosgene on phenylisocyanide, was
proved as follows : the imidechloride just named must give on
treatment with water oxanilic acid,

CH.N-C 0H

and of this substance not a trace could be found. In order to be ab-
solutely certain, oxanilic acid was made by the method of Klinger, $
as well as that of Aschan, § and thus its properties known by
actual experience. Incidentally it may be observed that on treat-
ing oxanilethane,

C6H5N=COH

OR

with alcoholic potash, according to the method of Klinger, J a new
unknown oxanilic acid was invariably obtained. It is readily
soluble in hot water, but very difficultly soluble even in hot ben-
zine; it crystallizes in needles, and does not melt at 210°. This
is probably a polymeric modification, because in other respects the
behavior is like that of oxanilic acid; it gives, for example, with

* Ber. d. chem. Ges., XXIV. 1243. t Ibid., XXIV. 867.

t Ann. Chem. (Liebig), CLXXXIV. 267.
§ Ber. d. chem. Ges., XXIII. 1820.

126 PROCEEDINGS OF THE AMERICAN ACADEMY

phosphorus pentachloride (one molecule) Asehan's* oxanil-chloride
melting at 82°, which, treated with water, gives the ordinary oxa-
nilic acid, melting at 149°.

C6H5N=C CI

Pyruvic-aniUdimidechloride, I

COCH3

If a mixture of 25 grams of phenylisocyanide and of freshly
distilled acetylchloride be heated on a boiling water bath, in a few
seconds so violent a reaction sets in that the entire mass carbon-
izes. The union of these substances can be accomplished quantita-
tively by taking a mixture of phenylisocyanide (10 grams) and
acetylchloride (8.2 grains), and placing it first in lukewarm water,
which is then gradually heated to the boiling point. The access of
moist air is prevented by means of calcic chloride tubes, and the
mixture shaken thoroughly, and, after the water once boils, heated
only for about two minutes and then cooled quickly.

Several portions thus prepared are then united, and diluted with
about five parts of absolute ether, whereby much or little polyme-
rized phenylisocyanide separates out in brown voluminous flakes.
After distilling off the ether from the filtrate, the dark brown
residual oil is distilled under diminished pressure. A yellow oil
was obtained, which distils with slight decomposition between
120°-125° at 20 mm. On redistilling, the chief portion came over
at 136° at 30 mm., and gave the following results on analysis: —

0.2356 gram substance gave 0.5256 gram C02 and 0.1042 gram

H20.
0.2463 gram substance gave 16.7 c.c. moist nitrogen at 17° and

747 mm.
0.1591 gram substance gave 0.1250 gram AgCl on ignition with

CaO.

Theory for C9H7NC10. Found.

C 59.50 60.83

H 4.41 4.91

N 7.72 7.73

CI 19.56 19.43

Pyruvic-anilidimidechloride is a yellow, very hygroscopic, sweet,
and at the same time sharp-smelling oil, which, freshly made,

* Ber. d. chem. Gcs., XXIII. 1823.

OF ARTS AND SCIENCES. 127

does not contain a trace of phenylisocj'anide. This is further
shown by its behavior towards water, whereby pyruvic anilide,

C6H5N=C

OH

)co,
en/

appears as the chief product, and no isonitrile is formed. The
imidechloride is, however, an extremely unstable substance, and
its preparation requires the greatest care; the phenylisocyanide
used must be twice distilled at reduced pressure, and even then it
may happen, especially if it is heated too long with the acetyl-
chloride, that on attempting to distil under diminished pressure
complete decomposition takes place. The imidechloride cannot
be kept long, but decomposes on standing in a desiccator into
phenylisocyanide and acetylchloride, the former substance at the
same time undergoing marked polymerization. As shown below,
the substance is decomposed by water into pyruvic anilide; on
pouring it into a small quantity of alcohol, marked evolution of
heat is noticed, and, on cooling, colorless leaflets of diphenyl-
formamidine hydrochloride (mpt. 255°) separate out. The free
base* obtained therefrom melts at 138°. This substance has such
marked properties, and was obtained so often in the work on iso-
nitriles, that an analysis was considered superfluous. The hydro-
chloride is especially characteristic; it dissolves in hot dilute
hydrochloric acid, and crystallizes out almost completely on cool-
ing (0°) in bulky hair-like needles, melting at 255°.

Very noteworthy is the totally different behavior of the imide-
chloride towards water and alkalies; for whereas it reacts with the
former, giving pyruvic anilide, according to the equation,

C6H5N=CC1 C6H5N=COH

I + H20 == I + HC1,

CH3-CO CH3-CO

it is split on pouring into dilute sodic hydrate, chiefly into the
components, as follows:

C6H5N=CC1 OH

I + H20 = C6H5NO + CH3CO + HC1,
CH3-CO

* Hofmann, Jahresber. 1858, p. 354.

128 PROCEEDINGS OF THE AMERICAN ACADEMY

16 grams of pyruvic-anilidimideehloride, for example, were di-
vided into two parts, and treated simultaneously as follows.

a. 8.3 grams were slowly poured into 200 c.c. of sodic hydrate
(1 : 10), which was kept at 0° by means of ice. A strong smell of
isonitrile is noticed immediately. After standing for an hour,
during which the mass was kept well stirred, it was extracted with
ether. The ether was then distilled off, and the residue distilled
with steam, the distillate thereupon extracted with ether, and, in
order to remove any aniline possibly formed, treated with dilute
sulphuric acid. After drying the ether solution with solid caustic
potash, there was left, after getting rid of the ether, 2.4 grams of
oil, which was practically pure phenylisocyanide.

b. 1.1 grams poured slowly into 110 c.c. of ice water solidified
quickly, and not a trace of phenylisocyanide was noticed. From
the solid mass 4 grams of pure pyruvic anilide (see below), were
obtained.

The same noteworthy difference in behavior towards water
and alkalies is also shown by mesoxanilidimidechloride (described
above). Whereas water converts it into mesoxanilidehydrate,
and not a trace of phenylisocyanide is observed, on pouring the
substance into dilute sodic hydrate (1:10), very much phenylisocy-
anide results. In an experiment carried out as above under a,
1 gram isonitrile was obtained from 4 grams of imidechloride.

This substance is therefore also split in two ways, according to
the conditions : —

1. With water,

C6H5N</ C6H5N=c£HOH

^CO + 3H20 = ;CX5 + 2HC1.

C6H8N=C^j C6H5N=C(3HUM

2. With alkalies,

P TT "N"=p

J ) CO + 2 H20 = 2 C6H5N=C= + C02 + H20 + 2 HC1.
C6HVN"=Cqj

This is, however, not at all a behavior peculiar to the two cases
mentioned, but seems to be a very general property of imidechlo-

OF ARTS AND SCIENCES. 129

rides. Wallach and his co-workers * have often noticed, in their
work on this class of substances, that on pouring amide and imide
chlorides into sodic hydrate, a strong smell of isonitrile appeared.
The amount formed was never determined, and they were unable
to offer an explanation for its formation; its appearance was sup-
posed to be due to the presence of some unknown impurity.

The above results make it probable that a new method for mak-
ing isonitriles is accessible through the alkylated acid amides,

.OH

r-c;

^NR

and phosphorus pentachloride. Up to the present time, however,
no further experiments have been carried out in this direction.

C6H5N=COH

Pyruvic Anilide, I

CH3-CO

In order to prepare this substance, it is not necessary to start
with pure distilled pyruvic-anilidimidechloride. The crude pro-
duct obtained by heating phenyl isocyanide and acetylchloride is
poured into a large amount of water, and in a short time the oil
solidifies, with marked evolution of heat. The mass is ground
to a fine powder, filtered off, and then crystallized once from boil-
ing water. Recrystallized once more from alcohol, a perfectly
colorless product is obtained, melting at 104°. The yield equals
generally in weight that of the isonitrile applied.

0.1697 gram substance dried over H2S04 in vacuum gave 0.4120
gram C02 and 0.0854 gram H20.

* Wallach, Ann. Chem. (Liebig), CLXXXIV. 75 and 75; in the case of

CI
C2H5N=C(

CO2C0H5

Wallach, Ann. Chem. (Liebig), CCXIV. 226; in the case of

.CI

CCI3
Klinger, Ann. Chem. (Liebig), CLXXXIV. 270, 276, 279, and 283 ; in the case of

C2H6N=cC

CI /yC\.2

C6H5N=CC and CGH5NH Cf

XC02C2H5 VC02C2H5.

VOL. XXVII. (n. S. XIX.) 9

130 PROCEEDINGS OF THE AMERICAN ACADEMY

0.2739 gram substance dried over H2S04 in vacuum gave 20.8 c.c."
moist nitrogen at 24° and 756 mm.

ory for C9H9N02. Found.

C 66.25 66.15

H 5.52 5.59

N 8.59' 8.47

Pyruvic anilide dissolves in large amount in hot, but very little
in cold alcohol. It is insoluble in cold water, and about 7 grams
dissolve in a litre of boiling water. It crystallizes in long color-
less needles, and is also soluble in chloroform and ether (in the
latter case not easily). The substance is very stable towards warm
dilute hydrochloric and sulphuric acids, and long boiling there-
with causes little change. Caustic alkalies, as well as ammonia,
act upon it immediately; although insoluble in sodic carbonate,
and giving no reaction to test paper, pyruvic anilide dissolves in
the cold in two molecules dilute sodic hydrate. On acidifying,
however, not the original substance is obtained, but a product
comes down in white flakes melting at 196° • This is in all prob-
ability a polymeric pyruvic anilide, and the reaction which takes
place is the following. At first, the pyruvic anilide, just as the
mesoxanilide above, takes up a molecule of water, forming the
hydrate

C6H5N=COH

CH3-Oqtt '

on acidifying, it loses water, and simultaneously with this, poly-
merization results. This becomes especially probable on compar-
ing the entirely similar behavior towards alkalies of oxanilethane
(page 125),

C6H5N=COH
I
R-O-CO

and of pyruvic-o-toluide (page 145),

CH3-C6H4-N=COH

I
CH3-CO

Attempts to split pyruvic anilide into pyruvic acid (in alkaline
solutions) were unsuccessful, although in every case almost the

OF ARTS AND SCIENCES. 131

calculated amovmt of aniline was obtained. The conversion into
pyruvic acid was accomplished finally in a roundabout way,
namely, by means of phenylhydrazine.

Pyruvic-anilide-phenylliydrazonehydrate,

C6H5N=COH

CH3-C°H

N NH-NHC6H5

On adding to a cold ethereal solution of pyruvic anilide one mole-
cule of phenylhydrazine, a voluminous white precipitate separates
out almost immediately in the form of needles. After filtering off,
washing well with ether, and drying a short time over sulphuric
acid in a vacuum, a perfectly pure preparation is obtained.

I. 0.1522 gram substance gave 0.3738 gram CO, and 0.0896
gram H20.
II. 0.1512 gram substance gave 0.3688 gram C02 and 0.0907
gram H20.
I. 0.1516 gram substance gave 21 c.c. moist nitrogen at 18°
and 748 mm.
II. 0.1506 gram substance gave 20.5 c.c. moist nitrogen at 18°
and 744 mm.

Theory for Found.

c

C15H17N302.

66.40

i.
66.98

ii.
66.52

H

6.30

6.54

6.66

N

15.50

15.74

15.38

Phenylhydrazine has thus simply added itself to pyruvic anilide,
just as in the case of mesoxanilide, as follows:

C6H5N=COH C6H5N=COH

I + H2NXHC6H6 =
CH3-CO CH3-C

OH

X NHNHCcHj

That the resulting substance is not a salt-like compound, but an
addition product, is certain, since alkalies do not split it into its
components. The hydrazonehydrate thus obtained loses on long
standing, or quickly at 70°, water going over into the hydrazone.
Heated quickly in a capillary tube it melts with gas evolution
(water) between 101°-105°, and then solidifies again, and melts on
further heating at about 160°.

132 PROCEEDINGS OP THE AMERICAN ACADEMY

C6H5N=COH

Pyruvic-anillde-phenylhydrazone, I

CH3-ON-NHC6H5

If the above hydrazone-hydrate be heated a short time in alco-
holic or in acetic acid solution, or pyruvic anilide be treated in
hot alcoholic solution with one molecule of phenylhydrazine, the
phenylhydrazone of pyruvic anilide is formed quantitatively. Re-
crystallized twice from alcohol, it is obtained in colorless needles,
melting at 176°, and after drying at 110° it gave the following
results on analysis : —

0.1508 gram substance gave 0.3930 gram C02 and 0.0819 gram

H20.
0.1736 gram substance gave 25.6 c.c. moist nitrogen at 17° and

734 mm.

Theory for C15H15N30. Found.

C 71.14 71.07

H 5.93 6.03

K 16.60 16.52

The hydrazone is easily soluble in hot benzine, alcohol, and
acetic acid, and comes out on cooling in colorless needles. It is
insoluble in alkalies or in dilute acids.

Phenylhydrazone of Pyruvic Acid, from Pyruvic Anilide.

The proof that the above compounds are in reality derivatives ot
pyruvic acid is as follows. 3.5 grams pyruvic - anilide pheny lhydra-
zonehydrate were treated with 120 c.c. sodic hydrate (1:10), and
heated in an open dish on a water bath for half an hour. The
formation of aniline was recognized by the smell, chloride of lime
reaction, and by conversion into acetanilide. After cooling and
filtering, the solution is acidified with dilute hydrochloric acid.
A very bulky precipitate, consisting of yellow needles (2 grams)
was obtained. It was dissolved in soda, reprecipitated by acids,
and finally recrystallized from alcohol. The product obtained
melted with decomposition at 192°, and was identical in every
particular with a preparation which was made according to the
directions of E. Fischer and Jourdan.*

* Ber. d. chem. Ges., XVI. 224, XVII. 578.

OF ARTS AND SCIENCES. 133

0.2018 gram substance dried over H2S04 in a vacuum gave 0.4515

gram C02 and 0.1061 gram H20.
0.1495 gram substance dried over H2S04 in a vacuum gave 20.8 c.c.

moist nitrogen at 17° and 748 mm.

Theory for C9H10N2O2.

Found.

c

60.68

61.01

H

5.62

5.84

N

15.73

15.88

Hydrochloride of Phenylbnidoformylehloride, 2GqK^s=C^ , HC1.

On passing hydrochloric acid gas, which has been dried by means
of phosphorus pentoxide, over phenylisocyanide, cooled to — 15°, so
violent a reaction takes place that it is not possible to regulate
it, even by diluting the gas with dry carbon dioxide. The ad-
dition of hydrogen chloride to the isonitrile can however be ac-
complished quantitatively, if the latter be diluted with 6 to 8
times its volume of absolute ether, and the dry gas be passed over
this solution, cooled to — 15°, until it smells of hydrogen chloride;
a white powder separates out, soon after the above operation is
begun, and after it is ended the mixture is allowed to stand fifteen
minutes. An equal volume of dry ligroine (bpt. 70° -80°) is then
added, the white precipitate is washed by decantation, and spread
out on porous clay plates, and transferred as quickly as possible to
a desiccator. After twelve hours' standing in a vacuum, it was
perfectly dry, and gave the following results on analysis : —

0.2193 gram substance gave 0.2939 gram AgCl (Carius).
0.2024 gram substance gave 0.2681 gram AgCl (Carius).
0.2875 gram substance gave 22 c.c. moist nitrogen at 20° and
750 mm.

Theory for
C12H,3N2C13.

Found.
I. II.

CI

33.75

33.11 32.77

N

8.87

8.64

That a salt of the formula 2 C6H5N=C=, 3 HC1, is formed, is proved
with greater precision even than by the analysis by the following
experiment. 20 grams phenylisocyanide treated as described with
hydrogen chloride, etc., gave 30.8 grams pure dry salt (calculated
30.6 grams). The salt thus obtained is a colorless powder, which
cannot be kept very long without decomposition; it is very hygro-

134 PROCEEDINGS OP THE AMERICAN ACADEMY

scopic, has a strong acid smell like an acid haloid, and is in-
stantly decomposed by water or alcohol with marked evolution of
heat. The salt dissolves in chloroform, but is insoluble in ether
and ligroine. Its behavior towards water and alkalies was carefully
studied. 16 grams were added slowly to 300 c.c. sodic hydrate
(1:10) kept at 0° by means of ice. Reaction instantly takes place,
and a portion goes into solution, another remains as a sticky gray-
ish mass. The mixture is immediately extracted with ether, and,
to get rid of any diphenylformamidine taken up by the ether,
washed with dilute hydrochloric acid. The ethereal solution is
then washed with soda, and dried with calcic chloride. After
distilling off the ether, 3 grams of an oily residue were obtained,
consisting chiefly of formanilide. On adding ligroine and cooling,
the formanilide solidified (2 grams), and recrystallized from a mix-
ture of ligroine and ether was obtained pure (mpt. 48°).

The above mentioned hydrochloric acid extract, as well as some
residue not extracted by the ether in the first place, contains diphe-
nylformamidine (mpt. 138°). 1.5 grams were obtained.

In an experiment where 15.8 grams phenylimidoformylchloride
salt and 180 c.c. of water were taken, and the experiment other-
wise carried out as above with sodic hydrate, 2 grams of formani-
lide and .4 gram diphenylformamidine were obtained.

The formation of diphenylformamidine in the two cases above
is easily explained by considering that aniline is split off; and, in
fact, the presence of aniline, as well as that of formic acid, in both
reactions was proved.

Gautier* also obtained, by treating methyl- and ethylisocyanide
with dry hydrogen chloride, salt-like products of the general for-
mula 2 KNC, 3HC1. He further found that they are instantly
decomposed by water and caustic potash, giving methyl- and ethyl-
formiamide respectively

.OH , OH

CH3N=C; and GJLN<r

XH XH

as chief products.

These experiments are sufficient to prove that the isonitriles
react with hydrogen chloride giving hydrochlorides of alkylimide-
formylchlorides,

2RN=C^, HC1.
* Loc. cit., XVII. 223 and 240.

OF ARTS AND SCIENCES. 135

On passing dry hydrogen chloride into a chloroform or an ethereal
solution of phenylisocyanide (cooled to — 15°) to which exactly one
molecule of alcohol has been added,* there is formed diphenyl-
formamidinehydrochloride, and not a trace of phenylformimido-
ether,

, OC2H5 f

The same result is obtained on treating an alcoholic solution of
phenylisocyanide (5 grams) with a few drops of alcoholic hydrogen
chloride.

Prussic acid reacts likewise with halogen hydrides, forming
white salt-like products. Thus Claisen and Matthews | have ob-
tained, by using acetic ether as a diluter, the salts 2 HXC, 3 HC1,
and 2 HXC, 3 HBr.

With regard to the nature of the products formed by directly
passing dry hydrogen haloids into anhydrous prussic acid, there is
no accord in the literature, especially in the case of the product
obtained with hydriodic acid. The last named substance was dis-
covered almost simultaneously by Gal § and by Gautier,|| and the
formula HXC, HI confirmed by both by means of analyses.

The description of the products obtained is however entirely dif-
ferent. Gal, on the one hand, describes his product as crystallizing
in wart-like aggregates, which are instantly decomposed by water;
whereas Gautier, on the other hand, states that his substance
crystallizes in rhombohedra, has a refreshing salty but not acid
taste; it is very soluble in water and in alcohol, with neutral reac-
tion to test paper, and crystallizes from the latter solvent without
decomposition. The substance is not hygroscopic, and sublimes
without melting at 350°-400°.

These are, however, pretty exactly the properties of ammonium
iodide; hence it follows that Gautier's supposed prussic acid salt
was nothing else than ammonium iodide. This becomes the more
probable because of the fact that Gautier, in his last paper f on
prussic acid, describes an addition product, HXC, HI, of entirely

* Pinner, Ber. d. chem. Ges., XVI. 354, 1644.
t Comstock and Clapp, Amer. Chem. Jour., XIII. 527.
\ Ber. d. chem. Ges., XVI. 310.
§ Comptes Rendus, LXI. 643.

|| Bull, de la Soc. Chim., IV. 88;. Comptes Rendus, LXI. 380.
TF Loc. at., XVII. 143.

136 PROCEEDINGS OP THE AMERICAN ACADEMY

different properties, without correcting his previous statements or
drawing attention to the difference. The results obtained in that
paper agree entirely with Gal's previous statements.

I have, therefore, also made this salt in large amounts from pure
prussic acid (bpt. 26°. 2) and hydriodic acid, dried by means of
phosphorus pentoxide, and can confirm Gautier's detailed state-
ments in Annales de Chimie et de Physique, [4.], XVII. 143, in
every respect. The substance is extremely unstable, and can only
be dried about a minute over sulphuric acid in vacuum; in ten
minutes such marked decomposition takes place that no analysis
of it can be carried out.

From the results obtained above in the case of the isonitriles,
and from the experiments of Claisen and Matthews, it becomes
very probable that all the salt-like products obtained from prussic
acid and the halogen hydrides are constituted according to the gen-
eral formula, 2 HNC, 3 HX. These compounds are, as Claisen
and Matthews * already regard as probable, salts of imidoformyl
haloids,

2 HN=C*Jj , HC1 ; 2 HX=C^r , HBr ; 2 HN=C ' , HI.

Gautier has already shown in his last paper f that hydrobromic
acid forms with prussic acid a salt of the formula 2 HXC, 3 HBr.
He thereby corrects his previous statements, as well as those of
Gal. It is, therefore, highly probable that the salts HNC,HC1,
and HNC, HI, analyzed formerly, may have contained mechani-
cally enclosed prussic acid, since the substances were only dried
a few seconds over sulphuric acid in a vacuum.

Furthermore, some new observations have been made which
make it improbable that imidoformylchloride,

HN=C^,

and phenylimidoformylchloride,

C6H5N=Cq2 ,

are capable of existence. It is to be expected that these substances
should be volatile liquids. On treating potassic formiate with
2 molecules of phosphorus oxychloride, or with 3 molecules of phos-
phorus trichloride, a violent reaction sets in at 0°, and a mixture

* Ber. d. chera. Ges., XVI. 311. t Loc cit., XVII. 141.

OP ARTS AND SCIENCES. 137

of carbonic oxide and hydrochloric acid results, which shows that
the forrnylchloride,

/H
OCT

XC1

first formed decomposes spontaneously.

On treating aniline potassium, C6H5NK2, (which is obtained as
a dark brown hygroscopic powder, on adding potassium to an excess
of aniline, and then heating the mixture in an atmosphere of
hj'drogen, first in order to dissolve the potassium, and finally to
get rid of the aniline, to a temperature of 310°,) with 1 molecule
of chloroform, a violent reaction takes place in the cold, but the
resulting product is not pheuylirnidoforinylchloride,

C6H5NK2 + CHC13 = C6H6N=C**,

but its decomposition products, phenylisocyanide and hydro-
chloric acid. The last named substance then unites with part of
the isonitrile set free to form the salt,

2C6H6N=c]?1, HC1.

The above observations are sufficient to clear up fully the re-
action which takes place on treating a primary amine with chloro-
form and caustic potash.* The amine P£NH2 forms at first with
the caustic potash present a mono- and a di-potassium salt, RNHK
and EJSTKo. These salts then react with the chloroform, giving
rise to the amide and imidechlorides,

^Cl2 H

RXH-CT and RN=C (

XH XC1

which are then converted by the caustic potash present into potassic
chloride and alkylisocyanide.

This noteworthy tendency to split off hydrogen and another
univalent group (here chlorine) from one and the same carbon
atom is not limited to the cases observed above. It is also, as is
known, a property of thioformanilide, f

.SH

c6h5n=c;

* A. W. Hofmann, Ann. Chem. (Liebig), CXLIV. 116.
t A. W. Hofmann, Ber. d. chem. Ges., X. 1097.

138 PROCEEDINGS OP THE AMERICAN ACADEMY

and, to a slight degree, as I have found, of formanilide,

.OH

c6h5n=c;

XH

on distillation. In these two cases, however, notwithstanding
many experiments, it was found impossible to attain a quantitative
splitting off of H2S or H20 respectively, because at higher tem-
perature the isonitriles polymerize to a marked extent.

A decomposition in the same direction has also been observed by
TVallach,* on distilling

OH

c2h5n<t

xC02C2H5
and by Klinger, f on distilling oxanilethane,

OH

c6h5x=c;

xC02C2H5

The formation of isonitriles and their polymeric products (resins)
in the above cases shows how strong a tendency exists for the split-
ting off in this direction. This same thing is to be seen in the
decompositions described above under pyruvic-anilidimidechloride
(pp. 127 and 128).

II. Ox o-ToLTLisocvANiDE, CH3-C6H4N=C=.

Prejiciration of o-Tolyllsocyanide. — 210 grams of caustic potash
are dissolved in about 800 c.c. alcohol (99%), and a mixture of
190 grams chloroform and 100 grams o-toluidine added slowly,
following in other respects the directions given under phenyliso-
cyanide.

Whereas, in the case of aniline only about 15 grams pure phenyl-
isocyanide are obtained from 100 grams of the amine taken, here
at least 25 grains pure o-tolylisocyanide always result.

o-Tolylisocyanide boils constant and without leaving any residue
at 75° at 16 mm., and at 101° at 55 mm. pressure: it boils with but
slight decomposition at 183°-184° (thermometer entirely in the
vapor) at ordinary pressure (753 mm.). It is a colorless oil, its
specific gravity being 0.968 at 24° (Westphal) : on standing, the

* Ann. Chem. (Liebig), CLXXXIV. 60.
t Ann. Chem. (Liebig), CLXXXIV. 265.

OP ARTS AND SCIENCES. 139

oil becomes colored pale greenish yellow. As regards smell and
physiological action, it closely resembles phenylisocyanide. It is
far more stable, however, than the lower homologue, and shows
little tendency to polymerize, even at 180°, and can therefore be
kept a long time without much change, except that the color changes
to dark yellow. The substance is readily volatile with steam.

0.1454 gram substance gave 0.4370 gram C02 and 0.0807 gram

H2G.
0.2499 gram substance gave 26.5 c.c. moist nitrogen at 22° and

75G mm.

Theory for C8H7N. Found.

C 82.05 81.97

H 5.98 6.17

N 11.97 11.95

Behavior towards Organic Acids. — On pouring 18 grams o-to-
ljlisocyanide into 2 molecules pure formic acid, cooled to 0°, a vio-
lent reaction sets in with evolution of pure carbonic oxide. The
residue consists of form-o-toluide, which boils at 286°, and crys-
tallizes from a mixture of ligroine and ether in six and eight sided
leaflets, melting at 62°. It is identical in every respect with a
form-o-toluide obtained directly from o-toluidine and formic acid
according to Ladenburg's direction.*

0.1744 gram substance gave 0.4567 gram C02 and 0.1060 gram

H20.
0.2044 gram substance gave 18.2 c.c. moist nitrogen at 15° and

752 mm.

Theory for CgHgNO. Found.

C 71.11 71.41

H 6.66 6.75

N 10.37 10.32

On mixing o-tolylisocyanide with 2 molecules of acetic acid
reaction sets in on warming gently : there is formed, after distil-
ling under reduced pressure, acetic anhydride and a mixture of
form-o-toluide and acet-o-toluide f (mpt. 10S°). Towards anhy-
drous oxalic acid o-tolylisocyanide behaves exactly like phenyliso-
cyanide. On heating o-tolylisocyanide with benzoic acid reaction

* Ber. d. chem. Ges., X. 1129. He gives the melting point, 56.°5-57.°5.
t Lehmann, Jahresber. 1882, p. 369. Beilstein, Kuhlberg, Ann. Chem. (Lie-
big), CLVI. 77.

140 PROCEEDINGS OP THE AMERICAN ACADEMY

takes place in an entirely analogous manner, and on distilling
benz-o-toluide (mpt. 142°) is obtained as the cbief product.

Molecular Rearrangement. — The conversion of o-tolylisocyanide
into o-tolylcyanide* takes place quantitatively on heating 4 c.c. of
the former in a sealed tube for three hours at 235°-245° (at 180°-
200° no change whatever takes place). 3 grams of o-tolylcyanide
were obtained, boiling at 202° -203° (thermometer entirely in the
vapor) at 728 mm. ; and from this, by saponification with sulphuric
acid, | o-toluylic acid melting at 104°.

Tbis molecular rearrangement has already been noticed by
Weith, j in the case of an o-tolylisocyanide containing o-toluidine.
Weith was in fact the first to prove that the alkylisocyanides,
KNC, go over by molecular rearrangement into the corresponding
alkylcyanides, HOIS". Gautier states, in a preliminary paper, § that
the boiling point of methyl and ethylisocyanide is raised after some
standing, and thinks that this is to be explained by a partial con-
version into methyl and ethylcyanide. In bis last paper || on the
isonitriles he says nothing whatever about this supposed molecular
rearrangement, but states that on long heating of methyl and
ethylisocyanide in sealed tubes at 200°, a portion polymerizes, but
tbat much unchanged isonitrile is left. A molecular rearrange-
ment in the case of the isonitriles has therefore only been proved
in the case of phenyl- and of o-tolylisocyanide. 1T

Action of Primary Amines. — 4 grains o-tolylisocyanide were
heated with reversed condenser with 4.4 grams o-toluidine for forty
minutes at 190°-220°. On cooling, no isonitrile smell was left,
and the dark brown solid residue was recrystallized four times from
alcohol; thus 2.2 grams perfectly pure o-ditolylformamidine,**
melting point 151°, were obtained.

0.2033 gram substance, dried at 110°, gave 22.5 c.c. moist nitro-
gen at 16° and 748 mm.

Theory for C15Hl6N2. Found.

N 12.50 12.69

* Cf. Weith, Ber. d. chem. Ges., VII. 722.
t Cahn, Ann. Chem. (Liebig), CCXL. 280.
\ Ber. d. chem. Ges., VII. 722.

§ Comptes Rendus, LXV. 862; Ann. Chem. (Liebig), CXLVI. 128.
|| Loc. cit., XVII. 226.

T Compare the discussion of Weith and Hofmann on this subject in Ber. d.
chem. Ges., VII. 722, 814, 1017, 1021.
** Ladenburg, Ber. d. chem. Ges., X. 1260.

OP ARTS AND SCIENCES. 141

If 10 grams of o-tolylisocyanide be heated with 1^ molecules of
aniline for twenty-five minutes at 190°-220°, the reaction is com-
pleted, and no isonitrile left. In this case, however, not only
phenyl-o-tolylformamidine,

.NHC6H6

ch5c6h4n=c;

results, but a mixture from which I succeeded only in separating
out diphenylformamidine as a pure product.

A similar result is obtained on heating 10 grams phenylisocyanide
with 10.5 grams o-toluidine for two hours at 190°-220° : from the
resulting mixture of amidine products, 0.4 gram of pure o-ditolyl-
formamidine (melting point 151°) could be isolated with ease.

These experiments show that the addition of primary amines
takes place somewhat more readily in the case of o-tolylisocyanide
than with phenjdisocyanide; and further, that the resulting dial-
kylated formamidine derivatives,

.NHR'
EN=Cf
XH

are homogeneous only when the two alkyl groups (R and E/) are
the same.

Action of Sulphur. — 5 grams o-tolylisocyanide and the calculated
amount of crystallized sulphur, in the presence of carbon bisulphide,
were heated in a sealed tube for two hours at 130°. No isonitrile
was left, and after distilling off the carbon bisulphide, the residue
was distilled with steam. The mustard oil thus carried over,
after extracting with ether and drying with calcic chloride, boiled,
on fractionating, at 236° -237° (thermometer entirely in the vapor)
at 726 mm. It was identical in all its properties with o-tolyl
mustard oil, * CH3-C6H4-N=C=S, and gave the following result on a
sulphur determination :

0.2681 gram substance gave 0.4064 gram BaS04 (Carius).

Theory for C8H7NS. Found.

S 21.47 20.81

Action of Hydrogen Sulphide. — An alcoholic solution of o-tolyl-
isocyanide was saturated at 0° with sulphuretted hydrogen, and

* Girard, Ber. d. chem. Ges., VI. 445.

142 PROCEEDINGS OF THE AMERICAN ACADEMY

then heated in a sealed tube for four hours at 100°. The hydro-
gen sulphide had completely disappeared, and, after distilling off
the alcohol, the residue was taken up with ether and shaken with
sodic hydrate. On acidifying the alkaline solution, thioform-
o-toluide separates out in yellow, bulky flakes; recrystallized three
times from ligroine (bpt. 70°-80°), using animal charcoal, it is
obtained in perfectly colorless needles, melting at 106°-101°. Se-
nier* describes thioform-o-toluide as a yellow substance, melting
at 94° -96° (crystallized from alcohol).

0.1986 gram substance, dried at 70°-80°, gave 0.2928 gram
BaS04 (Carius).

Theory for C8H9NS. Found.

S 21.19 20.29

Isocyan-o-tolylchlorlde or o- Tolylimidocarbonylchloride,
CH3-C6H4N=C=C12.

This substance is formed quantitatively on passing dry chlorine
into a chloroform solution of o-tolylisocyanide, as above in the case
of isocyanphenylchloride. As soon as the presence of unabsorbed
chlorine can be detected, the reaction is ended, and the solution
immediately washed with dilute sodic hydrate, and dried with
calcic chloride. On fractionating, a colorless sharp-smelling oil is
obtained, which "boils at 214°-215° (uncorr.).

0.1384 gram substance gave 0.2593 gram C02 and 0.0520 gram

H20.
0.2230 gram substance gave 15 c.c. moist nitrogen at 23° and

756 mm.
0.2103 gram substance gave 0.3201 gram AgCl (Carius).

Theory for CaH7NCl2.

Pound.

c

51.06

51.09

H

3.73

4.17

N

7.45

7.54

CI

37.76

37.65

o-Toluidine converts the isocyan-o-tolylchloride quantitatively
into o-tritolylguanidine hydrochloride. In order to isolate the
free hase, the solution is made slightly alkaline, and the excess of
toluidine got rid of by distilling with steam. The residue, recrys-
tallized twice from alcohol, gave flat needles of o-tritolylguanidine,

* Ber. d. chem. Ges , XVIII 2293.

OP ARTS AND SCIENCES. 143

NHC6H4CH3
CH3C6H4N=C(

NNHC6H4CH3

melting point, 131°.*

Lachniann f has described a substance as isocyan-o-tolylchloride,
wbicli he obtained by treating o-tolylmustard oil with chlorine,
according to the directions of Sell and Zierold. He studied it
but little, and gives the boiling point 218°, whereas the above
product boils at 214°-215°. That Lachmann's product was not
a homogeneous substance follows from the facts given above under
isocyanphenylchloride (p. 115).

Mesox-o-toluidehydrate = Dioxymalonic-o-toluide,

CH3C6H4-N-C°H

)C(OH)2.
CH3-C6H4-!N"=Cqjj

Phosgene reacts on o-tolylisocyanide energetically below 0°.
The union of these substances was accomplished as above in the
case of phenylisocyanide. In this instance, however, no attempt
was made to purify the resulting yellow imidechloride,

CHAH^C*?1

;co,

CH3C6H4N=C/-,|

by distillation. The crude product, after the excess of phosgene
had been removed by heating on a water bath, was directly poured
into a large amount of water : in* a short time, the imidechloride
is converted into mesox-o-toluidehydrate and hydrochloric acid,
with marked evolution of heat. The crude solid mass was first
recrystallized from benzine, and then dissolved in sodic hydrate,
precipitated again by acids, and finally recrystallized from much
hot water.

0.1530 gram substance, dried over H2S04 in vacuum, gave 0.3641

gram C02 and 0.0812 gram H20.
0.1920 gram substance gave 14.6 c.c. moist nitrogen at 16° and

762 mm.

* Berger, Ber. d. chem. Ges., XII. 1857.

t Ber. d. chem. Ges., XII. 1349. He does not state whether an analysis of
the product obtained was carried out.

144 PROCEEDINGS OF THE AMERICAN ACADEMY

Theory for CnH^N/^.

Found.

c

64.97

64.90

H

5.73

5.90

N

8.88

8.89

Mesox-o-toluidehydrate resembles in every particular the above
described rnesoxanilidehydrate. It is an acid, wbich reddens blue
litmus paper, and dissolves in dilute sodic carbonate. Heated
quickly in a capillary tube it becomes yellow at 100°, and melts
with gas evolution (water) at 127°-131°. About two grams
dissolve in a litre of boiling water, and, on cooling, tbe greater
portion comes out again in colorless needles. It dissolves in hot
anhydrous benzine with yellow color, which shows that dissociation
takes place, because on cooling (to 50°) the solution becomes color-
less. The substance, crystallizing out from hot benzine, on cool-
ing, never consists entirely of mesox-o-toluidehydrate, but contains
mesox-o-toluide as an analysis proved.

That no oxal-o-toluidechloride imidechloride,

CHsCeH^C^1 . CI

<o

is formed by the action of phosgene on o-tolylisocyanide is ex-
tremely probable, since, on decomposing the imidechloride obtained,
with water not a trace of oxal-o-toluidic acid,

CH3C6H4E--COH

. %H

was obtained.*

/CH3CGH4^COH\
TT-Pyruvic-o-toluide, I I In.

V CII3-CO '

o-Tolylisocyanide and freshly distilled acetylchloride (one mole-
cule) unite quantitatively, after five minutes' heating on a water
bath. The resulting yellow-colored imidechloride,

CH3C6H4N=CC1
I
CH3CO

* Mauthnerand Suida, Monatshefte fiir Chemie, VII. 234.

OF ARTS AND SCIENCES. 145

is in this case very unstable, and cannot be distilled under
reduced pressure, but dissociates to a marked extent into the
constituents.

On pouring the crude product (18 grams) into 130 c.c. of water,
cooling with running water, it becomes solid very soon. In this
case form-o-toluide is formed exclusively: 11 grams were obtained,
melting at 63°, and also confirmed by a complete analysis. The
imidechloride has therefore been decomposed according to the fol-
lowing equation :

CI

CH3-C6H4-N-C

/

+ 2H20=CH3C6H4N<£H + HC1 + CH3COOH.
CH3-CO M

This decomposition is not surprising when one considers that
pyruvic-anilidimidechloride is decomposed by alcohol in a similar
manner (p. 127); and although on treating this imidechloride with
water pyruvic anilide is the chief product (p. 129), formanilide is
also formed, but in slight amount only.

The above crude pyruvic-o-toluideimidechloride can however be
converted in part into pyruvic-o-toluide by pouring it into a
large amount of water. The yield is small (about 15%), and form-
o-toluide is present in larger quantiy, and it was not found possible
to effect a separation of these two products in a simple manner.
A polymeric pyruvic-o-toluide could however be isolated as fol-
lows. The crude imidechloride was poured into a large amount of
water, and allowed to stand for an hour. The mixture, consisting
also of some isonitrile, was extracted with ether, and the ethereal
solution treated with dilute sodic hydrate. The alkaline solution
was thereupon again extracted with fresh ether. On acidifying
nothing separates out, but ether extracts a substance, which is very
soluble in water (melting point 62°, crystallizing in six-sided
plates).

On drying the ethereal solution with calcic chloride, a flaky
substance all at once begins to separate out in large amount.
Recrystallized twice from alcohol, it was obtained in colorless
needles, melting at 177°.

0.2032 gram substance, dried at 110°, gave 0.5079 gram C02 and

0.1153 gram H20.
0.2244 gram substance, dried at 110°, gave 15.5 c.c. moist nitrogen

at 16° and 752 mm.
vol. xxvii. (n. a. xix.) 10

146 PROCEEDINGS OP THE AMERICAN ACADEMY

Theory for C10HnNO2.

Found.

c

67.79

68.16

H

6.21

6.34

N

7.91

7.97

The substance is insoluble in water and ether, easily soluble in
hot alcohol. It dissolves in dilute sodic hydrate, and comes down
unchanged on acidifying. It is probable that the above mentioned
substance, melting at 62°, is a hydrate,

CH3C6H4-N=COH

CH3-C

OH
OH

which loses water under the influence of the dehydrating agent,
calcic chloride, and at the same moment polymerization takes
place.

It has already been shown in an entirely analogous manner that,
on treating pyruvicanilide,

,OH

and oxanilethane,

C6H5N=CV
I
CH3CO

C6H5N=COH

C2H5OCO
with alkalies, polymerization takes place (pp. 125 and 130).

CH3C6H4X=COH

Benzoylformic-o-toluide, I

C6H5-CO

As was to be expected, benzoylchloride adds itself much more
slowly than acetylchloride to the isonitriles. On this account,
experiments undertaken with the object of adding benzoylchloride
to phenylisocyanide have not been successful. The addition takes
place very slowly at 100°, and at the same time so much polymeri-
zation (resin formation) results that the presence of benzoylformic-
anilide (not as yet known) could not be proved.

The case is quite different if o-tolylisocyanide be taken, instead
of the lower homologue, as this substance does not polymerize so
readily. Five grams o-tolylisocyanide and one molecule of benzoyl-

OF ARTS AND SCIENCES. 147

chloride were heated for a day on a water hath, and thereupon 6-8
volumes of hot ligroine (bpt. 70°-80°) added. This causes the
separation of polymerization products as resins, which are got rid
of by filtering hot.

After distilling off the ligroine, water is added in order to de-
compose the imidechloride,

CH3-C6H4-X-C

I '
C6H5-CO

formed. The mixture is then heated on a water hath until no
more smell of benzoylchloride is noticed. After extracting with
ether, and washing the ether solution with soda, it is dried with
calcic chloride. On concentrating and cooling, the ethereal solu-
tion benzoylformic-o-toluide separates out in large quantity (3.5
grams). Eecrystallized twice from ether and ligroine, it was ob-
tained in colorless needles (3 grams), melting at 108°. The sub-
stance burns with great difficulty on analysis, for which it was
dried at 80° -90.°

0.1566 gram substance gave 0.4313 gram C02 and 0.0792 gram

H20.
0.2557 gram suhstance gave 13 c.c. moist nitrogen at 14° and 754 mm.

Theory for C15Hi3N02.

Found.

c

75.31

75.11

H

5.44

5.61

N

5.85

5.93

Benzoylformic-o-toluide dissolves on gentle warming in sodic
hydrate, forming thus in all probability a salt of the hydrate,

CH3-C6H4-N=COH

(OH

On acidifying it comes down unchanged. It is insoluble in water,
hut easily soluble in hot ether and alcohol, and crystallizes out in
needles.

The suhstance is very stable in the presence of concentrated sul-
phuric or hydrochloric acid, even at 100°. Boiling with an excess
of sodic hydrate splits off o-toluidine, but no benzoylformic acid is
obtained in this way.

148 PROCEEDINGS OP THE AMERICAN ACADEMY

Benzoylform ic-o-toluide Phenylhydrazonehydrate,
CH3-C6H4N=COH

si it rivJ-H-

^6w5 ^NHNHC6h5

One molecule of plienylhydrazine is added to a lukewarm (30°)
very concentrated solution of benzoylforniic-o-toluide, and the mix-
ture cooled to 0°.

A white crystalline granular precipitate — the hydrazonehydrate
— separates out, which was well washed, dried on a porous clay
plate and finally for two hours over H2S04 in a vacuum.

0.1563 gram substance gave 0.4134 gram C02 and 0.0879 gram

H20.
0.1976 gram substance gave 20.6 c.c. moist nitrogen at 19° and

749 mm.

Theory for C21H21N302. Found.

C 72.62 72.13

H 6.05 6.25

N 12.10 11.90

Plienylhydrazine has thus simply added itself to the carbonyl
group present in benzoylformic-o-toluide,

C6H5=CO C6H5C v

I + H2NNHC6H5 = I x NHNHCCH6.

CH3-C6H4N=COH CH3-C6H4-N=COH

That no salt-like compound is formed in this case is shown by
the fact that sodic hydrate does not split it into the components.

The hydrazonehydrate loses water on standing, or very quickly
at 60°, and becomes yellow and sticky; also on heating much above
30° in solution it is converted into a yellow hydrazone, which was
not further investigated. 1.3 grams hydrazonehydrate were heated
gently in alcoholic solution with sodium ethylate (from 0.5 gram
sodium), and then the alcohol distilled off. After adding water
and extracting with ether, the alkaline solution was acidified with
hydrochloric acid, and a yellow bulky precipitate obtained. It was
filtered off, dissolved in soda, reprecipitated, and finally crystallized
from acetic acid. Yellow needles were obtained melting at 153°,
and identical in every respect with a product, benzoylformic acid
phenylhydrazone,

OP ARTS AND SCIENCES. 149

C6H5OMHC6H6
I
OCOH

which Elbers * first obtained from phenylglyoxylic acid and phe-
nylhydrazine. Hence it is proved that the above two substances
are in reality derivatives of benzoylforrnic acid.

III. On ^-Tolylisocyanide, CH3-C6H4-N=C=.

Preparation of p-Tolyllsocyanide. — This substance was obtained
from j>-toluidine, etc., exactly as above in the case of the ortho
derivative, except that the isonitrile was not distilled over with
steam, which probably would have been an advantage. 22 grams
crude ^>-tolylisocyanide were obtained from 100 grams of ^?-tolui-
dine; it was distilled twice under reduced pressure. In the first
distillation, a large amount of residue remained; on the second
distillation, the isonitrile came over at 99° at 36 mm., and no resi-
due was left. It is a colorless oil, which on standing becomes
colored greenish yellow.

0.1137 gram substance gave 0.3398 gram C02 and 0.0639 gram

H20.
0.2117 gram substance gave 22 c.c. moist nitrogen at 20° and

752 mm.

Theory for C8H7N. Found.

C 82.05 81.50

H 5.98 6.24

N 11.97 11.77

j9-tolylisocyanide has a smell which is markedly different from
that of the other two isonitriles obtained above; yet it is difficult
to describe in words the difference. The smell is at first pleasant
and aromatic, but also gradually excites nausea.

Isocyan-p-tolylchl oriole, or p- Tolylimidocarbonylchloride,
CH3-C6H4N=C=C12.

The preparation of this substance is entirely analogous to that of
the corresponding ortho derivative. A colorless sharp-smelling oil
is obtained, which attacks the eyes, and boils at 225°-226° (un-
corr.).

* Ann. Chem. (Liebig), CCXXVII. 341.

150 PROCEEDINGS OF THE AMERICAN ACADEMY

0.2486 gram substance gave 0.4661 gram C02 and 0.0861 gram

H20.
0.1855 gram substance gave 0.2865 gram AgCl on ignition with

CaO.
0.2704 gram substance gave 19 c.c. moist nitrogen at 22° and

750 mm.

Theory for C8H,NC12. Found.

C 51.06 51.13

H 3.73 3.84

N 7.45 7.85

CI 37.76 38.20

Isocyan-p-tolylchloride when treated with jo-toluidine is con-
verted into _p-tritolylguanidine hydrochloride. In order to obtain
the free base,

.NHC6H4CH3
CH3-C6H4-N=(r

XNHC6H4CH3

the solution is made slightly alkaline, and the excess of ^-toluidine
driven over with steam.

The residue was recrystallized from alcohol, and colorless needles
obtained, melting at 123°, and identical in every respect with a
2)-tritolylguanidiue obtained by Merz and Weith.*

Cokcluding Remarks.

A. On Geometrical Isomerism of the Hydroxylamine Derivatives.

The following new observations have been made in the above
experimental portion, which find application in many directions.

1. That a carbonyl group, ^C-O, can by the addition of water

attain strong acid properties (p. 123). 2. That a carbonyl group
always reacts with phenylhydrazine, forming in the first place an
addition product,

\ /0H
C

' XNHNHC6H5

(pp. 121, 131, 148). 3. A spontaneous or easy splitting off of HX,
H2S, H20, from one and the same carbon atom (p. 137). 4. The
conversion of imidechlorides,

* Zeitschrift fur Cliemie, 1868, p. 610.

OP ARTS AND SCIENCES. 151

EN=C '

by the elimination of alkylckloride, R'Cl, into isonitriles, EN=C=
(pp. 127, 128).

In this ca.se two carbon atoms bound singly to each other are
torn apart, which shows how strong a tendency must exist for a
decomposition in this direction. A similar reaction has already
been observed by myself in the case of dibenzoyl, diacetyl, and
dicarboxyl-acetacetic ether.*

That chloralhydrate and glyoxylic and mesoxalic acid contain
two hydroxy 1 groups bound to the same carbon atom is pretty gen-
erally regarded as proved. Very recently Zincke and Arustf have
shown that tetrachlor-o-diketohydronaphthaline forms hydrates and
alcoholates, where the water and alcohol respectively cannot be
present as crystal water.

There exist already a number of examples in chemical litera-
ture where a substance containing carbonyl groups attains thereby
acid properties. Thus, for example, triquinoyl, j C606 + 8 H20,
and leuconic acid, C505 + 4 H20, of which the last named has been
especially studied by Nietzki and Benckiser.§ These substances,
being strong acids, cannot contain all the water as crystal
water, but they are to be regarded as hydroxylated compounds ;
C606 + 8 H20, e. g., is very probably dodekoxyhexarnetlrylene,
C6(OH)12 + 2H20.

In a like manner diacetyl, CH3-CO-CO-CH3, which was discov-
ered almost simultaneously by v. Pechmann || and by Fittig,!" pos-
sesses marked acid properties. It can be separated completely
from alcohol by concentrating a sodic carbonate solution of it on a
water bath.** Diacetyl itself forms hydrates and alcoholates, de-
composed by sulphuric acid, which have as yet not been further
studied.** It follows, therefore, that this substance by taking up
water becomes an acid stronger than carbonic acid: it cannot be
decided yet whether the acid resulting has the formula

* Ann. Chem. (Liebig), CCLXVI. 101, 105, 107.
t Ibid., CCLXVII. 329.

t Nietzki and Benckiser, Ber. d. Chem. Ges., XVIII. 504, 1842.
§ Ber. d. Chem. Ges., XIX. 301.
|| Ibid., XX. 3163, 3213.
1 Ibid., XX. 3184.
** Ibid., XXI. 1411, 1412, v. Pechmann.

152 PROCEEDINGS OF THE AMERICAN ACADEMY

(OH), ^(OH)2 (OH),
CH3C CO3-CH, or CH3-C- C CH3.

The above observations also suffice to clear up the hitherto enig-
matic behavior of quinone toward hydrogen haloids and water.
Hesse * and Ciamicianf have shown that water converts quinone
into hydroquinone, while Levy and Schultz, j as well as Sarauw,§
have converted quinone by means of hydrobromic and hydrochloric
acid into chlor- and bromhydroquinone respectively.

I supposed formerly || that these reactions were to be explained
by an addition of water and halogen hydride respectively to the
two pairs of double bonds present in quinone.

That this, however, is not the case, will be soon shown in detail
by Mr. Clark. It seems to me, therefore, very probable that the
peculiar behavior of quinone towards water and hydrogen haloids
is due to the presence of the two carbonyl groups in this compound.
Two molecules of water or of hydrochloric acid add themselves to
quinone, forming

c(OH)2

CI
cOH

CH^

II

CH^

^"CH

II

C(OH)2

and

HC^

II
HC^

^CH

II

COH

CI
I. II.

which then lose H202 and Cl2 respectively, forming hydroquinone :
the chlorine set free then reacts further, giving chlorhydroquinone
and hydrochloric acid. That the intermediate products I. and II.
should lose H202 or Cl2 so readily, and go over into benzene deriva-
tives, is not surprising when one considers how easily A 2,5 dihy-
droterephthalic acid goes over into terephthalic acid.1T

The fact that a carbonyl group reacts with phenylhydrazine,
forming an addition product, as well as the behavior of this group
towards water and alkalies, suffices to throw an entirely new light

* Ann. Chem. (Liebig), CCXX. 367.
t Gazzetta Chim., XVI. 111.
t Ann. Chem. (Liebig), CCX. 133.
§ Ibid., CCIX. 93.
|| Amer. Chem. Journal, XIII. 427.
1 v. Baeyer, Ann. Chem. (Liebig), CCLI. 293.

OP ARTS AND SCIENCES. 153

on the reaction which takes place between benzil and hydroxyl-
aniine. As is well known, Auwers and v. Me3Ter have obtained
two isomeric benzilmonoxinies, and three isomeric benzildioximes.
They sought, in the first place,* to explain this isomerism by a
different grouping of the atoms in space, but soon gave up this
explanation as insufficient,! especially because of the observations
of Hantzsch. The latter, together with Werner, J has brought for-
ward a new hypothesis to explain this isomerism, which depends
upon the assumption that space isomers of trivalent nitrogen can
exist.

The experimental proof, however, upon which everything de-
pends, that the three dioximes, for example, have the same chemical
constitution, cannot be regarded as absolutely settled.

From the observations developed in this paper, hydroxylamine
(one molecule) will react with benzil, forming in the first place an
addition product,

/OH
C6H5C

l xNHOH

C6H5-C

OH
OH

which can then lose water (two molecules) in two different ways,
giving

C6H5-ONOH C6H5C=N N

I and q

C6H5-CO C6H5-C(

OH
7 oxime, I. a oxirue, II.

In a like manner two molecules of hydroxylamine will react on
benzil, forming first the addition product,

P XT p'-'H-

uw5 yHN0H

which can then lose two molecules of water in three different
ways :

* Ber. d. Chern. Ges., XXI. 946, 3510, XXII. 705.
t Ibid., XXIII. 2405.
t Ibid., XXIII. 11.

154 PROCEEDINGS OP THE AMERICAN ACADEMY

C6H6C=N C6H5-ON.

, o c«hs-c.noh

CsHs^NHOH C«H»<0H C«H»*NOH

a dioxime III. y dioxime IV. $ dioxirae V.

The oximes I., II. and III.— V., respectively, can naturally be
converted into one another without molecular rearrangement by the
addition of water or halogen hydride, and the splitting off again
in a different way. The entire experimental work of Auwers,
V. Meyer, and others, on the oximes of benzil was very carefully
studied, and not a single fact found therein which could not be
explained by the above formula?, which are chemically different.
This shows on what an uncertain basis the assumed geometrical
isomerism of these substances rests.*

A similar relationship exists in the case of the oximes of benz-
aldehyde : the a oxime is converted by means of hydrochloric acid,
as Beckmann f has shown, into a solid j3 isomer.

It is highly probable, in the first place, that the product obtained
with hydrochloric acid is not a salt, but an addition product,

/H
C6H5C — N-OH.

I H

CI

On pouring this into sodic carbonate, it loses HC1 in a different

way forming the oxid, j C6H5-C-£THOH, or /? oxime. That a

/\
splitting off of HC1 can take place in this manner, and often
spontaneously, has been shown above (pp. 136, 150).

The ready conversion of /3 benzaldoxime into benzonitrile is self-
evident in the case of the above oxid formula. Furthermore, the
simultaneous formation of nitrogen and oxygen ethers on treating
the ft oxime with alkyliodides § is also explained.

That the two oximes of benzaldehyde both contain a hydroxyl

* Cf. Claus, J. pr. Chemie, [2.], XLV. 1-20.

t Ber. d. Chem. Ges., XXII. 430.

t I propose the name oxid for the group -NHOH, leaving the name oxime
for the group =NOH : this is entirely analogous to the names hydrazide and
hydrazone for the groups 0(;H5NH-NH- and C,;H5NH-N=, respectively.

§ Goldschmidt, Ber. d. Chem. Ges., XXIII. 2176.

OP ARTS AND SCIENCES. 155

group was first shown by Goldschmidt,* and later proved with all
precision by Hantzsch.f Up to the present time no fact exists
which could be brought against the above formula for the /3 oxime,
and the great majority are explained more simply by it than by the
assumption of geometrical isomerism of the nitrogen. This suf-
fices to show on how uncertain a basis the assumption rests that the
two oximes of benzaldehyde are alike constituted.

Finally, the presence of geometrical isomerism has been assumed
in a number of cases where it certainly does not exist: so, for
example, in the case of the so called /3 oximidobutyric acid,

CH3ONOH

I
H2OC(\H

and its anhydride, J

CH,-C=N x

I )o.

H2C-CO

These substances cannot possess the constitution given them : it
follows with certainty, from the work on acetoacetic ether, § that
the substances have the following constitution,

CH3-CNHOH CH3-C-NHX

II and II }0,

HCC02H HC - OO

where a geometrical isomerism on account of the nitrogen is
impossible.

Also the two substances that have been described as oximido-
succinic acids, || are certainly of different chemical constitution.

Oxalacetic ether,

COoR-COH

II
C02R-CH

must react with hydroxylamine, just as acetacetic ether with phe-
nylhydrazine, and form an oxid of the constitution,

C02R-ONHOH

II
C02RCH

i. e. a fumaric acid derivative.

* Ber. d. Chem Ges., XXIII. 2176.

t Hantzsch, Ber. d. Chem. Ges., XXIV. 16.

J Ibid., XXIV. 497.

§ Ann. Chem. (Liebig), CCLXVI. 64 and 70.

|| Cramer, Ber. d. Chem. Ges., XXIV. 1198.

156 PROCEEDINGS OP THE AMERICAN ACADEMY

On the other hand, the product obtained from succinosuccinic
ether is alone to be regarded as oxiinidosuccinic acid,

C02H-ONOH

I
C02HCH2

That, however, the one product can, by addition of water or of
HC1, and the splitting off again of these reagents, be converted
into the other, is readily seen.

With regard to the so called geometrical isomeric dioximido-
succinic acids,* it can be said that the isomers discovered have not
been proved to have the same constitution. The above observa-
tions in the case of the oximes of benzil, as well as the possibility
of lactone formation, complicate matters here to such an extent
that much more experimental material must be at hand in order to
decide the question.

B. On the Nature of Prussic Acid.

From the above experiments, and the work on acetacetic ether,
it has become very probable that prussic acid has the formula
HN=C=, and, consequently, that the metal in its salts is bound to
nitrogen, M-NO.

The physical properties of prussic acid, boiling point 26. °2,
specific gravity 0.697, and the poisonous properties, all tend to
show that this substance is the first member of the isonitrile,
R-N=0, series. At present experiments are being undertaken with
the object of obtaining the actual formonitrile, H-ON, by the re-
duction of cyanogen chloride or iodide. It is to be expected that
this substance will be neutral, and that it will possess a much
higher boiling point and specific gravity than prussic acid.

Potassium cyanide, f K-N=C=, reacts with alkyliodides, owing to
the energy of the bivalent carbon atom present, chiefly as follows:

KNO + RI = KNO ( = N^C-K + KI.

XI

Addition Product. Alkylcyanide.

* Soderbaum, Ber. d. Chem. Ges., XXIV. 1215.

t It would be more logical to call this substance potassic isocyanide, since it
does not belong to the cyanogen (-ON), but to the isocyanogen (-N=C=) com-
pounds. It is however questionable whether such a change would be feasible
at present.

OP ARTS AND SCIENCES. 157

Simultaneously with this reaction, hut in subordinate amount, a
direct replacement of the potassium always takes place ; so that an
alkylcyanide results as the chief product, but an alkylisocyanide is
always noticed as a side product, as has been observed by Dumas,
Malaguti, Hofmann, Gautier, and others.

That the silver salt, AgN=C=, should show a different behavior
towards alkyliodides, is also very clear;* first, because silver is
less positive than potassium, and consequently the bivalent carbon
atom present in both salts must be less reactive in the case of sil-
ver cyanide; secondly, a direct replacement of the metal will take
place more readily in the case of the silver salt.

That, however, it may happen, even with the silver salt, that no
direct replacement of the metal takes place, is shown by the be-
havior of cyanide of silver towards acetyl- and benzoyl-chlorides.
In these instances, the isonitriles, CH3C0-N=O and C6Hr;C0-N=O,
are not formed, as Gautier f thought probable in 1869, but
CH3 COON and C6H5COON are the products % obtained.

There exists at the present time in organic chemistry an hy-
pothesis that a hydrogen atom bound directly to carbon can
attain acid properties when one or more negative groups are also
bound to the same carbon atom. It is said that the negative group
exerts an "acid-making" influence on the hydrogen atom, which
extends, however, only to hydrogen bound to the same carbon atom
as the negative radical.

This hypothesis has absolutely no justification, and is entirely
illogical. It has already been shown that a methylene group be-
tween two carbonyl groups, COCH2-CO, has no acid properties
whatever. § Furthermore, it is to be observed that in other cases,
where it has been assumed that a hydrogen atom bound directly to
carbon attains acid properties, the negative group present contains
either oxygen or nitrogen, e. g. in nitro methane,

CH3-Nf

and in HON. Now the groups CI, Br, and F are undoubtedly
more negative than the cyanogen group, -ON, and possibly more so

* Cf. Ann. Cliem. (Liebig), CCLXVI. 137.

t Loc. cit., XVII. 208.

} Claisen, Ber. d. chem. Ges., X. 845, XI. 620, 1563.

§ Ann. Chem. (Liebig), CCLXVI. 67 and 113.

158 PROCEEDINGS OP THE AMERICAN ACADEMY

than the nitro group, -N02 ; notwithstanding this, chloroform,
CHCI3, bromoform, CHBr3, and fluoroform, CHF3, although we
have in these instances three strong electro-negative groups hound
to a carbon atom containing hydrogen, are all perfectly neutral
substances ; whereas it has been assumed that in H-ON the pres-
ence of the group -1ST, which can be regarded as only very slightly
negative, renders the hydrogen bound to carbon acid in its nature !

It is highly improbable that sodic nitromethane possesses the
constitution CILJ^a-lSrOv * the formation of bromnitromethane,
CH2Br-N02, from it by means of bromine proves nothing with
regard to the constitution of the sodium salt.f

Assuming that nitromethane possesses the constitution CH3-N02,
it is very well possible that on treating it with alkalies water adds
itself (as in the case of a CO group) to the nitro group,

ch3-n(°h>2

^O
and that this is split off again in another manner,

CH2=N°H

^O

so that the sodium salt has the constitution

rONa
0

CH2=NV

\ 1

C. On Acetacetic Ether. {Supplementary.}

In the first place, it may be remarked that the addition of acid
haloids to isonitriles described above is to be regarded as a very
essential confirmation of my work on acetacetic ether, in which I
proved experimentally that in the action of alkyliodides, as well as
of acid haloids, on sodium acetacetic ether, not a direct replace-
ment of the metal, but an addition, takes place. The experiments
show that the double bond present in sodium acetacetic ether,

CH3-CONa
II
COoKCH

* V. Meyer, Ann. Chem. (Liebig), CLXXI. 33.
t Amer. Chem. Journ., XIII. 427.

OP ARTS AND SCIENCES. 159

is more reactive than the bivalent carbon atom present in the
isonitriles, RrN=C=, which must be due to the more positive condi-
tion of the molecule ; if, however, the copper salt,

CH3-COcu *

II
C02ECH

be taken, we have a substance whose reactivity is about the same
as that of the isonitriles.

The objection of v. Pechmann,f that silver acetonedicarboxylic

ether,

COoR-CHo-COAg
II
COoRCH

reacts with alkyliodides, forming the same product as the sodium
salt, is without weight, since it has already been proved t that
copper, lead, and mercuric acetacetic ether react with alkyliodides
and acid haloids, forming addition products, i. e. the metal is not
directly replaced. It is therefore to be expected that a silver salt
will show a similar behavior.

That in the case of silver salts the metal is not always directly
replaced is evident from the behavior of silver cyanide, Ag]ST=0,
towards benzoyl- and acetylchloride (vide p. 157, and cf. J. pr.
Chem. [2.], 42, 177).

Furthermore, the fact that acetonedicarboxylic ether forms a di-
potassium salt § cannot be considered as evidence against its hydrox-
ylated nature, since this salt can very well possess the constitution,

J^>C=CH-COK

HCC02R

V. Pechmann || has just proved, exactly as Claisen % had already
done in the case of ketoaldehydes,

Pv

R-COOCH
OH

* Means half an atom of copper Cu".
t Ber. d. chem. Ges., XXIV. 4097.
t Ann. Chem. (Liebig), CCLXVI. 59 and 121.
§ Ber. d. chem. Ges., XXIV. 4096.
|| Ibid., XXV. 1040.
IT Sitzungsber. der bayer. Akad. d. Wiss., XX. 463.

160 PROCEEDINGS OF THE AMERICAN ACADEMY

that formyl-acetic ether contains a hydroxyl group,

HCOH

II
HC-C02R

It seems to me, therefore, now only a question of time until it
will be generally accepted that the so called 1,3 and 1,4 dike-
tones, as acetylacetone, CH3COH=CH-CO-CH3, and acetonylace-
tone, CH8COH=CH-CH=COH-CH8, as well as acetacetic ether, are
hydroxylated compounds.

Although v. Pechmann has shown that sodic formylacetic ether,

HCONa

II
HCC02B

when treated with benzoylchloride, is converted into

HCOCOC6H5

II
HCC02R

i. e. that a direct replacement of the metal by benzoyl has taken
place, I have shown, on the other hand, in just as decisive a man-
ner, that, on treating acetoacetic ether salts, *

CH3-COM
II
HCC02R

with acid chlorides, no direct substitution of the metal takes place.

Furthermore, I have also shown some time ago that sodic suc-
cinosuccinic ether and sodic dihydrodioxypyromellithic ether, f
which substances are more closely related to acetoacetic ether than
formylacetic ether, behave towards alkyliodides and acid chlorides
in a different manner from sodic acetoacetic ether. This can only
be due to the fact that the double bond present in sodic acetacetic
ether is more reactive than in the other cases.

V. Pechmann's experiments, J where he treats sodic acetacetic
ether in aqueous solution with benzoylchloride, and with chloro-
carbonic ether, are to be regarded as a repetition of my experi-
ments, since the process of the reaction must be the same whether
the operation be carried on in absolute ethereal or in aqueous so-

* Ann. Chem. (Liebig), CCLXVI. 121.

t Ibid., CCLVIII. 261.

X Ber. d. chem. Ges., XXV. 410, 1045.

OF ARTS AND SCIENCES. 161

lution. The behavior of sodic acetacetic ether towards acetic
anhydride * can also he easily explained by a twofold addition.

Finally, the action of phenylhydrazine on acetacetic ether can-
not be regarded as taking place in a manner analogous to the three
cases discovered above (p. 150), i. e. that the first named substance
simply adds itself to the carbonyl group. Oxalacetic ether,

COoR-COH

II
C02R-CH

forms, as W. Wislecenus f has shown, with phenylhydrazine a
salt-like compound, which is instantly split into its components
by alkalies, whereas the three hydrazonehydrates described in this
paper are not changed by alkalies.

A number of the objections brought forward by Bruhl t seem to
show that he has not fully understood my work on acetacetic ether;
as, for instance, his remarks on the proof " that a methylene group
between two carbonyl groups possesses no acid reaction."

I have shown, 1st, that malonic ether is neutral, i. e. it pos-
sesses no acid properties ; 2d, that sodic malonic ether is instantly
decomposed by water, like sodiumethylate; 3d, that the free ma-
lonic ether shows a behavior entirely different from acetacetic
ether; and consequently, 4th, proved that malonic ether forms a
salt only in case sodic ethylate is present.

That many acids exist which do not react with sodium in abso-
lute ethereal solution, seems to weaken the above proof in Bruhl's t
opinion; but this fact has absolutely no bearing on the point un-
der discussion. If, on the other hand, it is proposed to discuss
the question whether a substance can be an acid, which is not
soluble in soda or caustic soda, or which is not thereby converted
into an insoluble salt, that is another matter.

Although Bruhl finds the refractive index of acetacetic ether to
be in favor of the ketone formula of this substance, I am able to
bring forward another physical property of this substance which
points to the contrary, namely, that acetacetic ether is an electro-
lyte, and therefore an acid; whereas malonic ether is a non-elec-
trolyte, and consequently not an acid.

This shows how uncertain the conclusions are which can be
drawn from the physical properties of a substance with regard to

* Loc. cit., XXV. 1046.

t Ber. d. chem. Ges., XXIV. 3006. \ Ibid., XXV. 366.

VOL. XXVII. (N. S. XIX.) 11

162 PROCEEDINGS OF THE AMERICAN ACADEMY

its chemical constitution, — as lias already been shown by the dis-
cussion on the constitution of benzene.

Finally, the following supplementary remarks are made with
reference to the paper on acetacetic ether.* The substance de-
scribed as phenylhydrazine /3-etbylic carboxylate (p. 107) is iden-
tical in every respect with Heller's phenylcarbazinic ether; f
recrystallized from water, the melting point 85° was obtained,
and the substance, owing to a slight oxidation, becomes colored.

The melting point of (1) methyl pyrrol (2) carboxylic (4) acetic
ether (page 86), is incorrectly given 186° ; it should be 168°.

It sbould also be stated that Franchimont and Klobbie $ have
succeeded, by employing a different method from mine (p. 113,
cf. also p. 106), in converting malonic ether into a nitro derivative.
I regret that this paper should have been overlooked.

The interesting paper of Conrad and Bruckner, § " Ueber die Ge-
schwindigkeit der Verlaufes der Acetessigather Synthesen,'> which
appeared after I had sent off my paper to the Annalen, is entirely
in accord with the results obtained in my work.

In the above work on bivalent carbon, which will be continued,
I have been most zealously assisted by Dr. M. Ikuta, to whom I
wish here to express my warmest thanks.

* Ann. Chem. (Liebig), CCLXVI. 52-138.
t Ann. Chem. (Liebig), CCLXIII. 278.

| Reeueil de trav. chim. de Pays Bas, VIII. 283 (1889); cf. Franchimont,
Revue Scientif., 1890.

§ Zeitsch. fiir physikal. Chemie, VII. 283.

OF ARTS AND SCIENCES. 163

XL

NOTE ON THE REPRESENTATION OF ORTHOGONAL

MATRICES.

By Henry Taber, Clark University.

Presented May 24, 1892.

If 4> '^ an orthogonal matrix of which — 1 is not a latent root,

wt may put

1 -,p
v — - •

" 1 + 0'
whence follows

tr Y = 1 ~ tr- * = 1-<^1 = till = _Y •
1 + tr.0 1 + 0-1 0+1

and wo have

1- Y
* = f+Y'

This is Cayley's well known representation of an orthogonal
matrix in terms of a skew symmetric matrix. If — 1 is a latent
root of <£, hut not 1, — 4> will he an orthogonal matrix of which
1 is a latent root, hut not — 1; therefore, — 0 may he represented
as above, giving

Thus the expression

1- Y

± r+r

will, for a proper value of the skew symmetric matrix Y, give all
orthogonal matrices except those which have as latent roots both
± 1. Such of these matrices as are real, and of which the multi-
jdicity of the latent root — 1 is even, and, more generally, any Teal
proper orthogonal matrix, can, I find, be represented as an ex-
ponential function of a real skew symmetric matrix.

164 PROCEEDINGS OP THE AMERICAN ACADEMY

Thus, if (f> is any real proper orthogonal matrix, a veal skew
symmetric matrix 0 can always be found such that

<£ = es,

where e denotes the base of the Napierian logarithms ; ee is of
course defined as the exponential series, which is convergent, and
for which an expression may be obtained by Sylvester's theorem.
This function of 6, for all real skew symmetric matrices, gives
only real proper orthogonal matrices. Therefore by taking succes-
sively all possible real skew symmetric matrices, all possible real
proper orthogonal matrices may thus be found.

POSTSCRIPT.

Rea\ improper orthogonal matrices are of two kinds: of the first
kind are those real improper orthogonal matrices of which unity
is not a latent root, or of which the multiplicity of the latent root
\inity is even ; real improper orthogonal matrices of the second
kind are those of which the multiplicity of the latent root unity
is odd.

If 4> is a real improper orthogonal matrix of the first kind, a
real skew symmetric matrix 6 can always be found such that

<j> = -e*.

This function of 8, for all real skew symmetric matrices, gives only
real improper orthogonal matrices of the first kind.

A real improper orthogonal matrix of the second kind cannot be
represented as a function of any real skew symmetric matrix.

Worcester, Mass., July 12, 1892.

OF ARTS AND SCIENCES. 165

XII

CONTRIBUTION FROM THE GRAY HERBARIUM OF
HARVARD UNIVERSITY.

DESCRIPTIONS OF NEW PLANTS COLLECTED IN MEX-
ICO BY C. G. PRINGLE IN 1890 AND 1891, WITH
NOTES UPON A FEW OTHER SPECIES.

By B. L. Robinson.

Presented by George Lincoln Goodale, June 15, 1892.

Cleome Potosina. Herbaceous, two feet high: stem purplish,
striate, moderately branched, minutely glandular-pubescent, armed
at the nodes with pairs of small stipular spines: leaves trifoliate;
petioles minutely but densely glandular-pubescent, I-I2" inches in
length; leaflets ovate-lanceolate or narrowly rhombic, mostly acute
or acuminate at the apex, acute at the base, puberulent under a
lens and minutely ciliate, 1-1^ inches long, 5-8 lines broad: floral
leaves numerous, simple, lanceolate or ovate-lanceolate, subsessile,
4-6 lines in length : peduncles slightly puberulent or smooth,
about 9 lines long: sepals linear-subulate, acute, reflexed during
anthesis: petals spatulate, white, 5 lines in length, the blade
about equalling the slender claw: stamens variable, sometimes
very unequal in the same flower, some or all of them much exceed-
ing the petals: stipe of the ovary 6-10 lines long; capsule linear,
pointed at each end, moderately curved, smooth, but with a fine
longitudinal striation, 1^-1| inches in length, 1|— 2 lines in thick-
ness: seeds striate and muricate. — Tamasopo Canon, San Luis Po-
tosi, June, 1890 (n. 3538). Near the South American C. diffusa,
DC, but distinguished by the long stipe of the ovary, slender-
clawed petals, long stamens, and longer linear pods. It is also
near C. aculeata, L., but is amply distinguished by its long-stiped
ovary and much exserted stamens.

Viola reptans. Rhizome short, bearing long fibrous roots:
stems numerous, glabrous, prostrate, 6-10 inches long, rooting at
the nodes: radical leaves broadly ovate, suborbicular, obtuse or
rounded at the apex, cordate, regularly crenate-serrate, smooth on

166 PROCEEDINGS OF THE AMERICAN ACADEMY

both sides, slightly ciliate on the margin, white-punctate above,
paler beneath, 1£ inches long, 1\ inches broad; petioles 1-3 inches
long, pubescent on the upper surface; cauline leaves smaller,
ovate, subcordate, more inclined to be pointed: stipules narrow,
either subentire or cleft into 2-3 linear acuminate segments: pe-
duncles glabrous: sepals lance-oblong, obtuse or acutish: petals
white lined with blue, smooth : valves of the mature capsule 4
lines long, twice the length of the sepals : seeds dark, smooth,
and shining. — Hills of Patzcuaro, Michoacan, November, 1890
(n. 3591).

Xylosma Pringlei, Rob. (P. A. A., XXVI. 164). Additional
specimens of this species collected at Las Ganoas, San Luis Po-
tosi, June and July, 1891 (n. 3727), give the following supple-
mentary characters. The mature (?) fruit red, spherical, 2 lines
in diameter, slightly elevated in the spreading calyx, crowned
with the short styles, 1-2 seeded.

Kosteletzkya digitata, Gray. Mr. Pringle's no. 3622, from
Tamasopo Canon, San Luis Potosi, collected in June, 1890, appears
identical with the type of this species discovered by Dr. Palmer on
the Yaqui River, Sonora, 1869. Mr. Pringle's specimen shows the
plant to be erect and over two feet in height. The cauline leaves
are divided into three linear-oblong, subequal lobes, and have in
addition two smaller auricles at the base; the leaves of the branches
are simply linear, or have auricles of varying length at the base.
The flowers in a dried state appear to be white with a yellow tint.

Casimiroa edulis, Llav. & Lex. Mr. Pringle's no. 3861, from
near Guadalajara, represents a form of this species with rather nar-
row sessile leaflets but three in number.

iEscHYNOMENE petr^ea. A tall erect annual, 4-5 feet in
height: stem subsimple, slender, finely striate, nearly smooth:
leaves alternate, appressed-silky especially when young, 2-3 inches
long; leaflets 15-25 pairs and an odd one, oblong, obtuse, sharply
mucronate, 3-4 lines in length: stipules linear, very acute, 1-3
lines long: inflorescence subterminal or the flowers crowded on
short, very glandular-pubescent lateral axes; bracts very small,
ovate, acute, very pubescent, deciduous: pedicels short, 2-3 lines
in length, they and the calyx glandular-pubescent or hirsute:
corolla yellow, striped with purple: pod stiped, very deeply parted
into 2-4 almost semicircular segments, pubescent especially on the
edges and at the nodes; segments thin, flat, 3 lines in diameter,
somewhat veiny, but the veins not prominent. — Rocky hills near

OF ARTS AND SCIENCES. 167

Guadalajara, May, 1891 (n. 5147). I am indebted to Mr. Hemsley
for the information that this plant is distinct from 2E. conferta,
Benth., and that it appears to be the same species as Seemann's
2189, collected in the Sierra Madre. In the Gray Herbarium
there is a similar plant collected by Seemann in the Sierra Madre,
and probably representing his 2189. It certainly seems to be spe-
cifically the same as Mr. Pringle's plant, although it represents a
somewhat different stage of growth. In it the leaves arise from
the stem, and the inflorescence is hirsute and less glandular. In
Mr. Pringle's plants the stem-leaves have all fallen, and the entire
foliage is crowded upon short secondary axes, giving the specimens
a rather different habit.

Vigxa luteola, Benth., var. angustifolia. Stem appressed-
pubescent: leaflets lance-linear, rounded at the base, 1^—2 inches
long, about 3 lines broad: petioles short, not an inch in length. —
Wet places near Guadalajara, May, 1890 (n. 3188).

Vigna strobilophora. Stem slender, flexuous, branched, cov-
ered with a fine soft pubescence : leaves pinnately trifoliate ; leaf-
lets ovate, acuminate, entire, rounded at the base, pubescent or
glabrate above, somewhat paler and soft-pubescent beneath, 2^-
inches long, half as broad; common petioles pubescent, 1£ inches
in length: peduncles axillary, rather stout, curved, bearing the
flowers in dense racemes: bracts large, ovate, sharply acuminate,
entire, scarious, finely striate, somewhat pubescent and ciliated
toward the apex, closely imbricated over the buds, deciduous:
pedicels single, silky-pubescent, 1-3 lines long: calyx campanu-
late, short, colored; teeth short and obtuse: corolla blue-purple,
6-7 lines in length; standard orbicular, slightly refuse, with two
scale-like appendages at the base; wings bluntly auriculate on the
upper side; keel bent nearly at right angles, the end then conspic-
uously curved inward: stamens diadelphous : style bearded on the
outer side near the end; stigma somewhat oblique. — Bluffs of
barranca near Guadalajara, September, 1891 (n. 5163). This spe-
cies is strongly characterized by its large closely imbricated
bracts. In its keel it is almost intermediate between Phaseolus
and Vigna.

Cesalpinia MULTiFLORA. A medium-sized tree, minutely seri-
ceous on the younger parts : foliage and racemes crowded near the
ends of the branches; leaves 7 inches or more in length, bipinnate;
pinnae about 10 pairs; common petiole striate-sulcate, 3 inches
long; leaflets 15-18 pairs, elliptic-oblong, mucronate, entire, mod-

168 PROCEEDINGS OF THE AMERICAN ACADEMY

erately oblique at the base, 4-6 lines in length, 1|— 2 lines in
breadth, paler beneath : racemes numerous, many-flowered, 6 inches
or more in length, flowering from near the base: flowers early de-
ciduous, leaving the rhachis naked below: pedicels 4-5 lines long,
articulated somewhat above the middle : calyx-teeth subequal,
ovate-oblong, smooth, yellowish brown, subcoriaceous, distinctly
but narrowly imbricated, 2-2^- lines long, retlexed in anthesis :
petals bright yellow, obovate, erose, 4-5 lines long, one of them
with a slightly narrower blade and broader claw, and bearing a
small crest-like appendage on the inside near the base: stamens
erect, equalling the corolla; filaments silky near the base; ovary
hirsute, about 6-ovuled: fruit not seen. — Volcanic hills, Monte
Leon Pass, Michoacan, Ma}r, 1891 (n. 3730). The very narrow
imbrication of the sepals tends to connect Caesalpinia and
Poinciana.

Lopezia angustifolia. Somewhat woody near the base: stem
purplish, nearly smooth, 2-4 feet high, giving off numerous slen-
der spreading subsimple branches : caulme leaves not persistent,
the lower not seen, the upper ones and those of the branches nar-
rowly lanceolate, irregularly subserrate, glabrous, 5-10 lines long,
1-2 lines broad, pellucid-punctate, narrowed to a bluntish point,
contracted at the base to a slender petiole (1^-3 lines in length),
midrib often reddish: racemes numerous, terminating the stem
and branches, not distinctly pedunculate; pedicels not exceeding
6 lines: calyx segments red, linear, narrowed to an obtuse point,
the lowest somewhat broader: petals purple, the lower ones obo-
vate, cuneate, 3 lines long, the upper with a linear-oblong blade,
scarcely at all auriculate at the base; glands single, very slightly
contracted in the middle: sterile stamen with filament not equal-
ing the suborbicular refuse bright-red blade : fruit spherical, 2
lines in diameter. — Limestone ledges of Las Canoas, San Luis
Potosi, October, 1891 (n. 3990).

COULTEROPHYTUM, n. gen. of the Umbelliferaa (Selinea?).
Stylopodium slender, conical; margin not distinctly undulate.
Fruit clavate, subterete in cross-section, contracted below the
seeds into a short winged stipe-like base; commissure broad; car-
pels compressed dorsally; the primary ribs narrowly winged, the
lateral wings slightly broader; oil-tubes single at the intervals,
about four on the commissure ; seed-face concave. — Tall perennial of
robust habit; leaves bi- or tri pinnate: inflorescence much branched;
umbels compound: bracts of the involucres and involucels several,

OF ARTS AND SCIENCES. 1G9

small, filiform. This genus appears most closely related to Ligus-
ticum, differing from it chiefly in the more slender conical stylo-
podia, solitary oil-tubes, carpels dorsally flattened, and fruit con-
tracted below. In its habit and lax inflorescence it somewhat
resembles Arracacia, but its much broader commissure and the
form of the seed would place it rather among the Selineae. I take
pleasure in dedicating the genus, at the desire of the discoverer, to
Professor John M. Coulter, who with Mr. J N Kose has so care-
fully elaborated the North American species of this difficult order.
To Mr. Rose I am indebted for kind assistance in determining the
generic affinities of the plant here described.

C. laxum. Stem somewhat woody, 5-10 feet high, an inch in
thickness, with prominent nodes ; leaves bi- or tripinnate, 18 inches
in length, with enlarged sheathing petioles; leaflets ovate or ovate-
lanceolate, serrate, acuminate at the apex, rounded at the base,
almost smooth above, pubescent on the veins beneath with minute
stiff hairs : inflorescence lax, several times branched, branches
bearing compound umbels with 6-12 rays : bracts of the involucre
1-4, sometimes wanting, short, filiform; bractlets similar, usually
more numerous: fruit 4 lines long; the contracted base a line in
length: flowers not seen. — Bluffs of barranca near Guadalajara,
September, 1891 (n. 3831).

Oldenlaxdia Pringlei. Caespitose: stems ascending or pros-
trate, subsimple or considerably branched, usually springing from
elongated scaly rhizomes : leaves pseudo-verticellate, in groups of
4-8, linear, acute, appearing somewhat fleshy : flowers borne in
rather loose terminal cymes: pedicels 1-3 lines in length: corolla
salver-formed, 4-lobed, 2-2^- lines long, purple in a dried state:
stamens and pistil dimorphous; anthers either inserted on the
middle of the tube or just exserted from its summit: ovary entirely
inferior, crowned in fruit by the lanceolate approximate calyx
teeth; these almost equalling the capsule in length: seeds smooth,
numerous, obtusely angulate, not concave. — Alkaline plains, Ha-
cienda de Angostura, San Luis Potosi, June, 1891 (n. 3758). A
plant of almost equal affinity to Oldenlandia and Houstonia, pos-
sessing the numerous small angulate smoothish seeds and entirely
inferior ovary of the former, but the dimorphous flowers and linear
anthers of the latter.

Crusea megalocarpa, Wats (P. A. A., XXVI. 137), Sper-
macoce megalocarpa, Gray (Ibid., XXI. 381). Mr. Pringle's
specimens of this species being in flower, the floral characters

170 PROCEEDINGS OF THE AMERICAN ACADEMY

which seem never to have heen described, may now be given.
Corolla smooth and (in a dried state) purplish-blue, 6 lines long;
tube very slender, limb of 4 linear-oblong lobes, spreading or
moderately reflexed : stamens and pistil conspicuously exserted,
anthers blue, curved, versatile. — On dry talus of cliffs in shade,
barranca near Guadalajara, September, 1891 (n. 3852). The elon-
gated corolla fully confirms Dr. Watson's view that this is a
Crusea, and not a Spermacoce.

Valeriana albonebvata. Tuber two inches in diameter: stem
erect, two feet in height, sulcate-striate, pubescent, subsimple up
to the branched inflorescence, nearly leafless : radical leaves numer-
ous, pinnate; leaflets 3-4 pairs and an odd one, broadly obovate
or suborbicular in outline, sometimes an inch in diameter, mostly
smaller, cuneate at the base; limb more or less divided into 3-5
broad rounded lobes ; the edges and veins beneath covered with a
short and dense white pubescence: petioles pubescent, 2-4 inches
long; cauline leaves 1-2 pairs, distant, much reduced; inflores-
cence regularly dichotomous; bracts awl-shaped, 1-1 jj lines long-,
flowers small; corolla a line wide, scarcely half as long: stamens
exserted: fruit ovate, glabrous, 2 lines long, crowned by the
spreading plumose calyx-teeth of the same length. — Hillsides,
San Jose" Pass, San Luis Potosi, July, 1890 (n. 3612),

Eupatorium filicaule, Schultz Bipontinus. Stem slender,
terete, striate, the upper part covered with a very short close pu-
bescence: leaves opposite, membranaceous, petiolate, ovate, sharply
acuminate, subcordate or somewhat hastate, serrate, nearly or
quite glabrous on both surfaces, 2 inches long, 1| inches wide:
petioles flexuous, pubescent, 9 lines or more in length ; inflores-
cence of slender opposite spreading branches, bearing numerous
sub-racemose heads; pedicels filiform, 1-1£ lines long, fasciculately
grouped upon the branches: bracts filiform, heads 2-§- lines long:
scales of the involucre 9-12, linear-oblong, sharply acuminate, the
two or three outermost much shorter than the others, all thin,
striate, tending to turn purple, minutely pulverulent-pubescent:
achenes somewhat clavate, puberulent at the angles, narrowed be-
low into a sort of stipe. — Near E. Palmeri, Gray, but differing in
its more delicate foliage, more racemose heads, and in the achenes
attenuated downward. This and the following seem to be good
species, which were named by Schultz Bipontinus, but, so far as I
have yet been able to learn, were never described. The description
above is drawn, not from the type which is Ehrenberg's no, 1176

OF ARTS AND SCIENCES. 171

(in the Berlin Herbarium), but from a specimen collected by
Schaffner in Orizaba, October, 1855. The latter plant was identi-
fied with Ebrenberg's by Schultz himself, who employed the ! sign
to express special definiteness. Bilimek's no. 576, Orizaba, May,
1867, and Bourgeau's 1703, Valley of Cordova, January, 1866,
have been identified with this sj^ecies by Dr. Gray. Mr. Pringle's
plants collected on ledges of the Tamasopo Canon, November aud
December, 1890 (nos. 3649 and 3956), are also certainly to be re-
ferred here, although the leaves are more deeply hastate.

Eupatorium Schaffneri, Schultz Bip. Boot a cluster of
thickened fibres: stems 2-3, terete, pubescent, tending to turn
dark purple, a foot or two in height, sparingly branched: leaves
opposite, petiolate, ovate, crenate-serrate, acutish, truncate at the
base, subglabrous, 1 J inches long, an inch wide : petioles 4-7 lines
in length, the upper shorter: heads corymbose, pedicellate, about
25-flowered, 1^ lines long (somewhat immature) : scales of the invo-
lucre equal, obtusish or more or less pointed, thin, sub-transparent,
but with 2-3 strong nerves in the middle near the base : achenes
immature. — Description drawn from the type collected by Schaffner
in Mexico near S. Angelos, 1855 (u. 28). In the Gray Herbarium
the following specimens may be referred to this species: Schaffner's
no. 292 ex convalli San Luis Potosi, August, 1876; Parry and
Palmer's 345, from a similar locality, 1878; and Pringle's 3662,
Flor de Maria, Mexico, October, 1890. These specimens, which
are more mature than the type, show the heads to be a trifle larger,
the ripe achenes to be small, dark, scarcely contracted below, pu-
berulent both on and between the angles.

Eupatorium Lemmoni. Stoloniferous : stems subsimple or
much branched, terete, dark purple, with close white pubescence :
leaves all opposite, sessile, mostly elliptic or ovate-elliptic, obtus-
ish, 10-14 lines long, about half as wide, crenate-serrate (some-
times obsoletely so), glabrous above, sparingly pubescent upon the
veins beneath: the lower leaves smaller, rounder; the uppermost
more ovate and acute: heads 3^ lines high, on peduncles half an
inch in length: the sharply pointed nearly smooth scales of the
involucre subequal: flowers rather numerous; corollas white;
achenes somewhat puberulent. — First collected by Mr. J. G. Lem-
mon in the Chiricahua Mountains of Southern Arizona, 1881
(n. 316 in part) ; then by Dr. Edward Palmer in Southwestern
Chihuahua, August to November, 1885 (n. 332) ; and by Mr.
Pringle on cool rocky slopes of the Sierra Madre, September, 1887

172 PROCEEDINGS OF THE AMERICAN ACADEMY

(n. 1264). Mr. Lemmon's specimens were supposed by Dr. Gray
to belong to E. Rothrockii, with which they had been associated,
and it is to them that he referred (Syn. Fl. I. 2. 102) in speaking
of depauperate forms of E. Rothrockii with sessile leaves.

Xanthocephalum tomentellum. Perennial, 2-3 feet high:
stem simple, leafy up to the corymbose inflorescence, striate, to-
mentulose: leaves entire, thickish, pale green, glabrate above,
tomentulose beneath; the radical ones oblanceolate or spatulate,
rounded at the apex or obtusely pointed, 2-2^ inches in length,
narrowed at the base to petioles 3-4 inches long; the cauline ob-
lanceolate; the lower contracted below into broad more or less
clasping petioles; the upper sessile, acute: branches of the inflo-
rescence angulate, bearing the heads in rather dense terminal cor-
ymbose groups : heads 2|— 3 lines long, about as broad; involucre
campanulate;' scales regularly imbricated in several rows, abruptly
pointed, the scarcely thickened ends appressed or slightly spread-
ing: rays numerous, not exceeding the disk flowers: pappus in
both ray and disk flowers a crown of short unequal scales more or
less united into a cup ; achenes glabrous, 2-edged, with or without
one or two intermediate angles. — Alkaline meadows, Hacienda de
Angostura, San Luis Potosi, July, 1891 (n. 3761).

Bellis purpukascens. Perennial: root of numerous fibres:
stem procumbent, much branched, angulate, striate, covered with
spreading white pubescence: branches simple or again divided,
terminating in long slender simple peduncles : leaves elliptic lan-
ceolate or the lower somewhat spatulate, acute or acutish, entire,
sessile tending to turn purple, 8-18 lines long, 3-5 lines broad,
pubescent on both sides and ciliate : heads including the rays 7-8
lines in diameter: involucre spreading, the bracts in two series,
lanceolate, acuminate, herbaceous in the middle, with margins some-
what scarious (not so distinctly so as in B. integrifolia) : rays pur-
plish white: disk deep yellow. — Shaded grassy slopes, barranca of
Las Canoas, San Luis Potosi, August, 1891 (n. 3819). This plant
was distributed as B. xanthocomoides, Gray (Brachycome xantho-
comoides, Less.), the material of that species in the Gray Herba-
rium being insufficient to prove the distinctness of Mr. Pringle's
plant. I am indebted to Prof. N. L. Britton for definite infor-
mation on the subject, and for the kind loan of Schiede's no. 206
from the Herbarium of Columbia College, which shows B. xantho-
comoides to be certainly distinct, differing in its much less robust
and branching habit, its solitary heads, long slender runners, more

OF ARTS AND SCIENCES. 173

decidedly spatulate leaves, and the absence of the coarse spreading
pubescence.

Erigeron heteromorphus. Amphibious, glabrous throughout :
stems dark-colored, subsimple, rooting for some distance along a
decumbent base : leaves of two very distinct forms, those of the
terrestrial specimens three-lobed to the middle, sessile by a cune-
ate base, 2 inches long, an inch or more broad; the lobes lacini-
ately cleft: leaves of the sterile aquatic stems linear, elongated,
subentire or more or less divided, 4 inches or more in length:
heads including the rays 7-8 lines in diameter, borne singly on
peduncles 3-4 inches in length: involucre of subequal moderately
imbricated flat smooth green subulate scales with very narrow
scarious margins : rays about 50, narrow, pure white. — Growing
from calcareous tufa, more or less submerged, Cascades of the Con-
cepcion River near Micos, San Luis Potosi, December, 1891
(n. 3963). A remarkable species near E. scaposus, DC, but
strongly characterized as well by the smooth green scales of its
involucre as by the presence of the floating leaves.

Melampodium longipilum. A span or more high, cymosely
branched almost from the base : stem rather stout, the young in-
ternodes white with soft long spreading hairs, the older parts
pilose but much less densely so: leaves ovate or somewhat rhom-
bic, obtuse or rarely acute, contracted at the base and narrowly
connate, entire, appressed-pubescent, punctate, 2-2^- inches long,
half as wide : peduncles slender, very pubescent : bracts of the in-
volucre distinct, obovate, pointed, hirsute over the whole outer
surface: rays about 10, deep yellow, 2-3 lines in length: fertile
bracts laterally tuberculate-roughened, bearing a small acuminate
recurved appendage at the summit : disk somewhat elevated in the
centre. — San Jose Pass, San Luis Potosi, July, 1890 (n. 3639).
This plant stands very near M. divaricatum, DC, of which it may
possibly prove to be a well marked variety. It differs, however,
in its very hairy stem, and in its involucral bracts, which are not
only narrower and more acute, but are pubescent-hirsute over the
entire outer surface, instead of being merely ciliate, as in M. divari-
catum. Furthermore, the leaves are entire and incline to be more
obtuse, while the fertile bracts are very tuberculate and are pro-
vided with longer appendages.

Sabazia Michoacana. Perennial, 2-3 feet high: stem slen-
der, purple, hirsute-pubescent, somewhat branched, springing from
a short horizontal rootstock : leaves opposite, ovate-lanceolate, ser-

174 PROCEEDINGS OP THE AMERICAN ACADEMY

rate, acute at the apex, obtusish at the base, more or less distinctly
3-nerved, pubescent above, canescent-tomentose over the whole sur-
face beneath, 1|— 2 inches long, 7-9 lines broad: petioles short,
pubescent; bracts of the loose corymbose inflorescence small, lance-
linear, 3-4 lines long: heads about a dozen, including rays 6-8
inches in diameter; scales of the involucre ovate, acute, the outer
somewhat shorter, the inner longer, narrower, more oblong and
mure acute, but scarcely acuminate : rays about 10, white, tube
hirsute-pubescent, ligula broadly elliptic, 3-toothed, 3 lines long:
disk flowers yellowish white (?), tube hirsute-pubescent, limb 5-
toothed: anthers entire at the base: style tips with short blunt
appendages: achenes small, black, oblanceolate in outline, hispid-
ulous : pappus none. — Mountains near Patzcuaro, Michoacan,
November, 1891 (n. 4099). Distinguished from S. Liebmanni,
Scbultz Bip. ex char.,* by having heads loosely coiymbose, not
solitary, leaves ovate-lanceolate not elliptic, tomentose over whole
surface beneath instead of along the nerves.

Gymnolomia canescens. Stem striate-furrowed, branched,
leafy below, nearly leafless above, clothed with a close gray
more or less deciduous pubescence, and sparingly villous : leaves
opposite, ovate, subcordate, entire, acute or obtuse, triply nerved,
2-3^- inches long, roughish-pubescent above, canescent beneath
with silky appressed hairs; petioles 6-8 lines long: inflorescence
of several slender naked branches, each bearing 1-8 rather closely
aggregated heads (4-5 lines in diameter) : pedicels and bracts of
the involucre canescent, the latter lanceolate, acuminate, rather
loosely imbricated in 2-3 series, the outer somewhat shorter:
rays 5-7, yellow, not exceeding the disk: chaff ovate-lanceolate,
carinate, terminating in acute pubescent points, with or without
lateral teeth: style branches of the disk flowers with rather at-
tenuated tips: achenes dark, mottled with light color: pappus
none. — Brackish marsh, Las Tablas, San Luis Potosi, June, 1890
(n. 3611), and alkaline plains, Hacienda de Angostura, San Luis
Potosi, June, 1891 (n. 3763). This species differs from the other
Gymnolomias which I have examined, in having more attenu-
ated style tips, but it appears better placed in this genus than
elsewhere.

Tithonia brachypappa. Stem terete, striate, smooth or nearly
so, branched above : branches terminating in peduncles thickened

* Klatt in Leopoldina, XXIII. 2.

OF ARTS AND SCIENCES. 175

upward and subscabrous ; cauline leaves alternate, 2-2^ inches in
diameter, deeply 3-lubed, broadly cordate, scabrous above, pubes-
cent beneath, lobes serrate, acuminate, the middle one more or less
pandurif orm : petioles 9 lines long, winged: wings decurrent for
some distance upon the stem: heads exclusive of the rays an inch
in diameter: involucre hemispherical; bracts striate, with subfolia-
ceous tips, the outer shorter, rounded at the apex, the inner equal-
ling or slightly surpassing the disk, acute: raj^s about 8-10, deep
yellow, 9 lines long; chaff scarious, carinate, very sharply acumi-
nate, with or without lateral teeth: achenes 4-angled but decidedly
compressed, narrowed downward, dark in color, often mottled with
light red: pappus none or in the same head consisting of a ring
of short unequal rather rigid teeth. — Las Palmas, San Luis Potosi,
October, 1890 (n. 3675). This plant has so perfectly the habit
and characters of a Tithonia that it should certainly be referred to
this genus notwithstanding its short sometimes obsolete pappus.
From T. tagetiflora, Desv., it differs in its involucre; from T. dir
versifolia, Gray, in its considerably smaller heads and shorter rays,
as well as in achenes and pappus.

Verbesixa Potosina. Stem rather stout, furrowed, pubes-
cent, leafy to the summit: leaves alternate, lance-oblong, attenu-
ate, acute, sessile, auriculate, denticulate on the subrevolute edges,
roughish pubescent above and finely dotted with the enlarged white
bases of the hairs; white tomentose beneath, less so on the veins:
heads rather numerous, 5-6 lines in diameter, loosely corymbose,
peduncles pubescent, 1-3 inches in length: scales of the involucre
lanceolate, sharply acuminate, canescent, rather loosely imbricated,
not equalling the disk flowers ; rays about 12, very small, scarcely
exceeding the involucre, yellow : disk strongty convex : chaff scari-
ous, keeled, pubescent near the acuminate tips : disk flowers deep
yellow: achenes oblanceolate, 1^ lines in length, notched at the
summit and with a slight angle on each face; wings moderately
broad, upwardly ciliate, subacute above. — Mesas, Hacienda de An-
gostura, San Luis Potosi, July, 1891 (n. 5113). Near V. auricu-
lata, DC. (ex char.), but differing in its radiate heads, narrower
leaves, and lanceolate acuminate involucral scales.

Verbesina Pringlei. Fruticose: branches covered with a
whitish cortex; branchlets strongly angled, glabrous or nearly so:
leaves opposite, lanceolate, attenuate, acute, rather coarsely and
irregularly serrate-dentate, of harsh texture, scabrous above, pu-
bescent but scarcely rough beneath, 3-5 inches long, 1-1^ inches

176 PROCEEDINGS OP THE AMERICAN ACADEMY

wide, narrowed below to short petioles : cymes few-headed, scarcely
or not at all exceeding the upper leaves: pedicels }2-l inch in
length, pubescent: heads discoid, orange-yellow, 5 lines high, about
12-flowered: bracts of the involucre about 10, the outer oblong or
spatulate, obtuse, scarcely half the length of the flowers, the inner
more or less acute: corolla hispidulous upon the outer surface:
achenes black, with broad wings and two nearly erect awns : heads
of fruit subglobose : the plicate chaff with bright yellow curved tips
exceeding the achenes. — Dry rocky bluffs of barranca near Guada-
lajara, September, 1891 (n. 3845). This species differs from V. ser-
rata, Cav., in its shrubby habit, narrower leaves, somewhat smoother
stem, etc. Berlandier's no. 1289, collected at Monte San Juan del
Rio, November, 1827, is evidently nearly related to Mr. Pringle's
plant, but the specimen is too fragmentary for certain identifica-
tion; there appear to be slight differences in the achenes, and the
heads of Berlandier's plant do not have the chaff conspicuously
curled in fruit.

Spilanthes Beccabunga, DC, var. parvula. Root a cluster
of thickened fibres: stems several, decumbent, 4-6 inches high,
rooting at the lower joints : leaves ovate, entire, including petiole
only 6-10 lines long, half as broad: heads a little smaller and rays
shorter than in the typical form: anthers dark, slightly caudate at
the base. — Wet soil, Flor de Maria, State of Mexico, August,
1890 (n. 3643). This may perhaps be a distinct species.

Spilanthes disciformis. Stem prostrate, woody, verrucose,
rooting at the joints, and sending up numerous subsimple, more or
less fleshy, glabrous, purplish branches : leaves lance-oblong or lance-
linear, triply-nerved, entire, glabrous, 10-14 lines long, 1^-3 lines
wide, usually considerably exceeding the internodes, narrowed to a
blunt point, contracted below to a short, sometimes ciliated petiole:
peduncles at the ends of the branches, striate, glabrous, 2 inches
long: scales of the involucre ovate (not lanceolate nor oblong),
acute, subciliate : rays yellow, inconspicuous, scarcely exceeding
the involucre, the heads at first sight thus appearing discoid: re-
ceptacle much elevated: disk flowers yellow: anthers entire at the
base: achenes black, ciliate at the angles, and slightly hispid on
the faces, exaristate. — Wet meadows, near Guadalajara, May,
1890 (n. 3489). A stout, somewhat fleshy species, differing from
S. Beccabunga in its more woody stem, narrower entire leaves,
shorter rays, ovate scales, and entire anthers.

Leptosyne pinnata. Acaulescent: root of several thickened

OF ARTS AND SCIENCES. 177

fibres : the base of the plant covered with brown wool, as in some
species of Cacalia : leaves including petioles a foot in length, pin-
nate, glabrous ; leaflets 4-6 pairs and an odd one, elliptic-lanceo-
late, acute at each end; the terminal one much larger, 8-10 lines
long, obscurely crenate, with minute glands in the sinuses of the
crenation; scapes a foot high, simple or branched, bearing one or
more linear bracts : involucre double, the outer bracts narrowly ob-
long, exceeding the broader inner ones, all obtuse : heads solitary,
exclusive of the rays \ inch in diameter: rays white, 4-5 lines
long, fertile : disk flowers yellow, their corollas destitute of an
annulus at the junction of the tube and throat: achenes slightly
ciliate on or near the summit, but without a distinct pappus. —
Wet meadows, Del Rio, State of Mexico, August, 1890 (n. 3668).
This plant approaches most nearly the genus Leptosyne, differing
from it, as heretofore limited, chiefly in its white rays and in the
absence of an annulus on the disk corollas. The neighboring
genera, Dahlia and Bidens, show, however, what variation is to be
expected in the color of the rays, and in L. Mexicana, Gray, which
Dr. Gray pronounces a good Leptosyne, there is scarcely a trace of
an annulus. Mr. Pringle's plant is certainly very distinct in its
habit from any known species of the genus.

GEISSOLEPIS, n. gen. of the Compositse (Galinsogese).
Heads heterogamous, radiate. Flowers all fertile, rays white, disk
yellow. Involucre turbinate-campanulate ; scales ovate, obtuse,
closely imbricated in 4-5 rows, the outer regularly shorter. Re-
ceptacle chaffy in all parts, but not alveolate; chaff obovate, ob-
tuse, ciliate. Disk flowers regularly 5-toothed, throat not enlarged.
Anthers entire below. Style divided nearly to the middle; the
branches flattened, bearing short conical appendages. Achenes 4-
angled, pubescent, crowned with 7-8 very acute awl-shaped, mi-
nutely and retrorsely ciliated scales. — A prostrate, somewhat
succulent herb, with alternate entire linear leaves: heads small,
solitary on lateral peduncles arising opposite the leaves. This
genus is perhaps best placed just before Blepharipappus. The
generic name, derived from yda-aov and \enls, has reference to the
well imbricated scales of the involucre, one of the distinctive char-
acters of the genus.

G. su^edjefolia. Stems prostrate, giving off numerous sub-
simple branches : branches 4-6 lines in length, finely pubescent,
especially at the nodes: leaves glabrous, fleshy, 6-8 lines long,
half a line in breadth, sessile: heads including rays 8 lines in

VOL. XXVII. (n. s. xix ) 12

178 PROCEEDINGS OF THE AMERICAN ACADEMY

diameter; rays elliptic, 3-toothed, 2-3 lines in length. — Alkaline
plains, Hacienda de Angostura, San Luis Potosi, June, 1891
(n. 3762).

Plaveria anomala. A glabrous annual, a span high: stem stri-
ate-angulate, much branched- leaves linear or lance-linear, grad-
ually narrowed to a slightly connate base, acute, 1^—2 inches long,
1^-2^ lines wide: heads numerous, aggregated at the ends of the
branches in dense corymbs, very small, subtended by minute dark-
tipped bracts, 1- (rarely 2-) flowered; the single flower either tubular
or ligulate: involucral scales of unequal breadth, lance-linear or
oblong, more or less narrowed but obtuse at the apex, persisting in
fruit and becoming swollen and bulbous on the back near the base :
corollas bright yellow; in the tubular flowers the campanulate
throat and spreading limb equalling the tube, the latter hairy on
the outer surface; the ligules a line or less in length: achenes
oblanceolate, ribbed, black. — Plains, Vanegas, San Luis Potosi,
September, 1890 (n. 3669). This interesting plant was first col-
lected by Dr. C. C Parry in Northern Mexico, 1878 (n. 31), and
again the same year en route from San Luis Potosi to San Antonio,
Texas (n. 500) ; but Dr. Parry's specimens were determined (prob-
ably by Mr. Hemsley) as F. linearis, Lag. "forma morbida." Dr.
Gray noted the specimens as a new species, but appears never to have
described them. Mr. Pringle's plants, collected twelve years later
and agreeing closely with Dr. Parry's, seem to show that they rep-
resent a permanent species, and not merely a casual form. In its
very few-flowered heads this species approaches F. repanda, Lag.

Porophyllum Pringlei. A smooth pruinose annual, l£- 2 feet
in height: stem terete, simple below, branching above: leaves
elliptic, subentire, with rounded apex and acute base, delicate in
texture; the cauline mostly opposite, 1-2 inches long, half as
broad, on slender petioles of nearly equal length; the rameal
mostly smaller, inclining to be alternate: glands of the leaves
few, all marginal, broadly elliptic, light brown: heads rather few,
scattered, 9 lines in length, tapering and very acute in bud: scales
of the involucre narrow, | of a line in breadth, acuminate, with
scarious margins and a single median row of glands : peduncles aris-
ing singly: flowers fews about 12, little or not at all exceeding the
involucre: corolla tube very slender, about equalling the achene in
length; the limb very small, nearly white. — Barranca near Gua-
dalajara, September, 1889 (n. 2954) ; also in a similar locality,
October, 1891 (n. 5168). This species is near P. Ervendbergii,

OF ARTS AND SCIENCES. 179

Gray, but differs in its scattered, not at all cymose heads, and
larger, thinner entire leaves glandular only on the margins.

Cnicus excelsior. Very tall, 6-10 feet high: stem ribbed,
partially covered with a deciduous arachnoid pubescence: lower
leaves lanceolate, acute, subentire, somewhat repand toward the
base, spinulose-ciliate, 8 inches long, 2 inches broad, narrowed be-
low into a petiole 2-3 inches in length, pale green and more or less
arachnoid above, covered beneath with a thin gray arachnoid to-
mentum; cauline leaves sometimes a foot or more in length and 5
inches in breadth, siuuate-pinnatifid, with triangular, acute lobes,
spinulose on the edges, sessile and conspicuously decurrent in broad
wings (3—4 inches in length): inflorescence branching; the branches
bearing toward their summits several small rather closely aggre-
gated heads: heads in an thesis 7-8 lines, in fruit 1 inch broad;
scales of the involucre appressed, regularly imbricated, narrowly
ovate, narrowed above or somewhat abruptly contracted to a short
ascending or spreading yellowish spine, and bearing near the apex
just beneath the spine a dark glandular (?) streak; the inner bracts
longer, narrower, very acute but unarmed, purplish : corollas purple,
the narrow throat contracted very gradually into the slender tube;
limb not very oblique : filaments hairy : style branches short, not
exceeding f of a line in length; annulus inconspicuous. — Among
shrubs, low lands, Hacienda de Angostura, July, 1891 (n. 3768).
Near C. altissimus, Willd., which it resembles in its soft, weakly
armed leaves of varying form, closely also in its involucre and the
color of its flowers, as well as in its tall habit. It differs, however,
in its strongly decurrent leaves, smaller, more numerous, and closely
aggregated heads, shorter style branches, and less oblique corolla.

Perezia Michoacana. Stem slender, striate-angulate, glabrous,
dark purple, 4-6 feet in height, bearing a loosely corymbose, rather
few-headed inflorescence : leaves obovate-spatulate, sharply denticu-
late, rounded at the apex, auriculate-clasping at the base, glabrous,
veiny, thickish, and somewhat rigid; the lower ones 6 inches long,
half as broad; the upper smaller and more inclined to be acute;
those of the inflorescence much reduced, 3-9 lines in length, lin-
ear-oblong, acute: heads § of an inch high, 40-flowered: scales of
the involucre dark purple, fulvous-tomentose on the edges, imbri-
cated in 5-6 ranks and varying greatly in length, the outer being
very short, but all acute: corolla purplish: style branches recurved:
immature achenes linear, striate, glandular-roughened. — Hills
near Patzcuaro, Michoacan, December, 1891 (n. 3988). This spe-

180 PROCEEDINGS OF THE AMERICAN ACADEMY

cies stands near P. rigida, Gray, but differs from it in its more
numerously flowered heads, in the character of the involucre, and
somewhat in the shape of the leaves. The heads, however, are not
so large as in P. formosa, Gray, and P. turbinata, Llav. & Lex.,
nor do the involucral bracts extend down upon the peduncles as in
these species.

Androsace (?) cinerascens. A spreading perennial of grayish
green color, 6-10 inches in height, a little woody at the base : stems
ascending, several times branched, very leafy: leaves narrowly
linear, acute, sessile, perhaps slightly fleshy, 1-1| inches long, £-§
of a line broad : peduncles slender, smooth, 3-4 inches long, bear-
ing 4-8 corymbosely grouped flowers; pedicels ebracteolate, fili-
form, 6-8 lines long : the short calyx tube hemispherical ; segments
lanceolate, acuminate, corolla small, salver-shaped, 2 lines long,
white or nearly so : capsule enclosed by the persistent calyx, dehis-
cent by 5 valves: placenta spherical, raised on a very short stipe:
seeds numerous, minute. — Alkaline plains, Hacienda de Angos-
tura, San Luis Potosi, July, 1891 (n. 3765). This plant, which
is very different in habit and inflorescence from any Androsace
which I know, appears nevertheless to agree with that genus in all
essential characters of flowers and fruit. The genus as described
by Bentham and Hooker is rather widely drawn. The species just
characterized agrees more nearly with § Aretia than with Euandro-
sace, but differs from both in its inflorescence.

Dictyanthus tuberosus. Root thickish, enlarged and fusiform
toward the end, resembling a small tuber: stem short, somewhat
woody, erect or procumbent, bearing near its summit several sub-
simple spreading hirsute branches : leaves ovate, acuminate, entire,
deeply cordate, with a narrow but rounded sinus, pubescent on both
surfaces and ciliate, l-l£ inches long, on hirsute petioles 4-7 lines
in length: flowers occasionally solitary, usually 2-4 together, with
or without a short common peduncle ; pedicels 2-4 lines long : calyx
divided nearly to the base into lanceolate acuminate hirsute seg-
ments, 3-4^ lines in length: corolla campanulate, 4-6 lines deep:
tube marked with narrow purple stripes; limb of spreading tri-
angular segments of dark color, and but 2-3 lines in length: folli-
cle narrowly lanceolate in outline, about 2 inches long, tapering to
a bluntish apex, armed with short, firm spines, and appearing striate
from numerous minute longitudinal folds of its outer integument. —
Slopes of barranca near Guadalajara, September, 1890 (n. 3568).
First collected by Dr. Edward Palmer near the same locality, July,

OP ARTS AND SCIENCES. 181

1886 (n. 251). Dr. Palmer's specimen was referred by Dr. Gray
(P. A. A., XXII. 436) to D. stapelicefiorus, since it accorded with
Reichenbach's exceedingly defective description. The additional
notes and excellent plate of that species in Kegel's Gartenflora,
Vol. VI., however, show clearly that it is altogether different, with
larger, somewhat undulate leaves, much shallower corolla tube, and
broader differently colored limb. Mr. Pringle's specimen and one
of Dr. Palmers show no tendency toward a climbing habit; but a
detached branch with Dr. Palmer's no. 251 has longer, flexuous
internodes, suggestive of such a character. The flowers on this
branch are larger, and the common peduncles longer.

Gonolobus suberiferus. Stem covered with a thick rough
light yellowish corky bark: branches, petioles, and peduncles cov-
ered with a spreading pubescence: leaves ovate, acuminate, deeply
cordate, with a narrow, often closed sinus, pubescent on both sur-
faces and ciliate, lj— 2 inches long, 1 inch broad: petioles an inch
long: peduncles about half as long, each bearing a single pedicel
an inch in length : catyx segments ovate-oblong, acute, pubescent
and finely granular on the outer surface, ciliate, nearly smooth
within, corolla 1^ inches in diameter; segments ovate, obtuse,
yellowish green, very minutely granular, otherwise smooth, exceed-
ing the calyx by half, not conspicuously marked or veined : top of
column white : crown dark brown : follicles slender, smooth, more
than 3 inches in length, the calyx persistent at its base. — San
Jose Pass, San Luis Potosi, July, 1890 (n. 3631).

Phacelia namatostyla. A small, slightly fleshy annual:
stems numerous, short, 2-3 inches in length, prostrate, branching,
pubescent: leaves bipinnatifid, 8-12 lines in length; pinnae about
seven pairs and terminal one, oblong, obtusely lobed, covered above
with a fine gray pubescence, smoothish below, except the midrib;
margins strongly revolute : racemes numerous, dense, not exceeding
the leaves ; bracts minute or obsolete ; flowers very small : calyx
lobes oblong-spatulate, corolla white, a line in length, campanulate
with slightly spreading limb of five rounded lobes : stamens inserted
upon the lower part of the tube, scarcely equalling the corolla; fila-
ments smooth: style divided nearly to the base; summit of the
ovary pubescent; ovules two on each placenta, pendent; capsule
globose, shallowly sulcate in the middle of each of the two valves ;
seeds dark brown, one line in length, conspicuously pitted. — Car-
neros Pass, Coahuila, May, 1890 (n. 3493). This species is anoma-
lous in its style, which is divided practically to the base, as in

182 PROCEEDINGS OF THE AMERICAN ACADEMY

Nama. Its much divided leaves, however, would not go well in
that genus.

Cordia alba, P. & S. Mr. Priugle's specimens of this species,
collected at Las Palmas, San Luis Potosi (nos. 3676 and 3754) have
light yellow flowers as in Wright's 425 from Cuha and Fendler's
921 from Venezuela. No. 3754 has short stamens and consider-
ably longer styles, thus representing the complementary form to
that of Ghieshrecht's 832 and Wright's 425 with exserted stamens
and short styles. Darwin * found the difference in the length of
the stamens in an undetermined Cordia very slight, the anthers in
both forms being " seated in the mouth of the corolla. " Here, how-
ever, the difference is very noticeable, the stamens of the short-
styled form being considerably exserted from the throat, although
not exceeding the limb of the corolla.

Lithospermum calcicola. A cinereous perennial : a foot or more
in height, several-stemmed from a branching distinctly ligneous
base: stems covered with a spreading hirsute pubescence, subsimple
and naked below, branched and very leafy above : leaves elliptic, ob-
tuse, slightly mucronate, sessile, 12-15 lines long, 3-4 lines broad,
appressed-pubescent on both sides, white-punctate above ; the upper
ones similar but somewhat smaller: flowers very small, subsessile:
calyx segments lance-linear, densely hirsute, in anthesis scarcely
more than a line in length, in fruit 2-3 lines long: corolla very
short, scarcely exceeding the calyx : nutlets ovate, more or less con-
spicuously keeled on the inner surface, usually only one maturing,
dark brown, shining, deeply pitted, becoming nearly 2 lines long.
— Limestone ledges, San Jose Pass, San Luis Potosi, July, 1890
(n. 3529). This plant considerably resembles L. Matamorense, DC,
but differs in its ligneous distinctly perennial base. Its stems are
rather more leafy above, the leaves less contracted at the base, and
the nutlets slightly larger.

Lithospermum revolutum. Perennial : stems one or several
arising from a single thickish root, simple or somewhat branched,
pubescent, scabrous: lower leaves falling off; the middle and upper
stem-leaves thick, oblong or elliptic, entire, revolute on the edges,
rounded at the apex, sessile, very scabrous above, pubescent and
scarcely paler beneath, 1-2 inches long, 3-7 lines broad: inflores-
cence rather dense; bracts ovate, ciliate, acute, 4 lines long, not
equalling the calyx lobes; flowers short-pedicelled : calyx lobes

* Different Forms of Flowers, pp. 117, 118 (orig. edit.).

OF ARTS AND SCIENCES. 183

linear, nearly equalling the tube of the corolla; the latter appar-
ently yellowish, 4-5 lines in length, with small only slightly
spreading limb: style exserted; nutlets small, shining, white or
discolored, scarcely keeled. — Alkaline meadows, Hacienda de An-
gostura, San Luis Potosi, July, 1891 (n. 3802). Distributed as a
form of L. striatum, Lekni., equalling Schaffner's no. 728. A more
careful examination shows that it is not very near Schaffner's doubt-
ful plant, and is certainly distinct from L. strictum, which has
linear acute leaves, narrow bracts, and keeled nutlets. Mr. Prin-
gle's no. 3245, distributed last year as L. strictum, probably also
represents a new species. It is much more robust than L. strictum,
and has a fusiform root more than half an inch in thickness.

Ipomcea orxithopoda. Glabrous, stem slender, twining, an-
gulate, dark colored: leaves very deeply palmately or rather sub-
pinnately 5-7 parted; lobes linear, 1^-2 inches long, 1-2 lines broad,
obtuse, apicuiate, entire or wavy; the edges revolute; petioles 6-8
lines long: peduncles springing from most of the axils, but many
of them abortive; the developed ones 2-3 inches long, one-flowered;
pedicels | inch long, somewhat thickened upward: sepals orbicular,
thin, 5-6 lines in diameter, rounded or even retuse at the summit,
purplish on the margins : tube of the corolla very short, included
in the calyx, limb 1^-2 inches in diameter, with a broad open
throat, appressed-villous on the outer surface, color uncertain: fruit
not seen. — Hills, Canoas, San Luis Potosi, July, 1890 (n. 3553.)

Gerardia punctata, Kob. (P. A. A., XXVI. 172). Additional
specimens of this plant, collected at Carneros Pass, Coahuila
(n. 3682), and Las Canoas, San Luis Potosi (n. 3938), show that it
is probably perennial. The corolla sometimes attains a length of
16 lines. The name was unfortunately chosen, since the punctate
character of the calyx appears to be exceptional, and perhaps due
to the presence of a fungus. Notwithstanding its seemingly peren-
nial nature and longer flowers, this species may prove to be the
G. dasyantlm, Cham. & Schl., insufficiently characterized in
Linnsea, V. 104, and DC. Prod., X. 517.

Beloporoxe fragilis. Stem 3-5 feet high, somewhat branched,
smooth, scarcely striate, strongly contracted above the nodes and
readily disarticulating in a dried state; the transverse lines con-
necting the bases of the petioles often bearing a tuft of hairs,
especially in the younger parts of the plant: leaves ovate, acumi-
nate, blunt at the apex, obtuse or rounded at the base, li-3 inches
long, nearly half as broad, minutely pubescent above, nearly smooth

184 PROCEEDINGS OF THE AMERICAN ACADEMY

below, only the axils of the veins bearing tufts of white hairs:
petioles ^—1 inch long: inflorescences axillary, opposite, racemose;
bracts few, small, lanceolate; bractlets minute, subulate; calyx
glandular-pubescent, of five lance-linear segments, 2 lines long:
corolla pubescent on the outer surface, reddish, strongly veined,
nearly an inch long; tube narrow; lips subequal, the upper erect,
emarginate, the lower spreading, with three very shallow rounded
lobes: stamens close to the upper lip, inserted rather low down on
the tube; anther cells nearly equal in size, one inserted higher
than the other and oblique, both with a small white spur at the
base : fruit not seen. — Limestone ledges, Las Canoas, San Luis
Potosi, October and December, 1891 (n. 3933).

Habenaria Pringlei. Roots mostly fibrous, but the central
one tuberous: stem 3 feet high: leaves sheathing, ensiform, cari-
nate, 6-8 inches long, an inch in breadth, gradually tapering to a
long point: bracts lanceolate, sharply acuminate, 2 inches long,
5 lines broad; flowers about 10, large, pedicels 18 lines long; the
ovary of equal length : sepals ovate, acuminate, minutely cuspidate,
8-9 lines in length; the upper one erect, scarcely at all galeate;
lateral petals 2-cleft to the base, the segments linear, acute, the
upper broader, not equalling the sepals; the lower very narrow,
more than an inch in length: lip 3-cleft nearly to the base, exceed-
ing an inch in length; the segments all narrow and linear, the
lateral somewhat surpassing the thickish, scarcely acute central
one : fleshy processes very conspicuous, linear-spatulate, 3-4 lines
in length : spur over 5 inches long, exceeding the ovary and ped-
icel, its tip sheathed in the bracts and apparently adherent to
them. — Near Guadalajara, June, 1891 (n. 3823). This striking
species is related to H. macroceratites, Willd., and H. set if era,
Lindl., but differs from the former in its much longer narrower
leaves, larger flowers, and conspicuous fleshy appendages; from the
latter, by its larger more numerous flowers, and in the shape of its
petals.

Tigridia pulchella. Bulb small, oval, \ inch in diameter, with
a few fibrous roots at the base : stem slender, flexuous, 6 inches
to a foot high, bearing about two narrow linear acute plicate
leaves: spathe of two nearly equal lanceolate acute bracts 18
lines long, 5 lines broad : flowers solitary, about an inch in
diameter: pedicel slender, an inch in length: ovary 4 lines
long: outer segments of the perianth ovate-oblong; the lower part
slightly broader, light colored and spotted with purple, the blunt

OF ARTS AND SCIENCES. 185

crose somewhat recurved tips very dark purple, almost black; the
inner segments shorter, more narrowed below, and with a broad
yellowish minutely granular fold in the middle, the obtuse tips
purple but not so dark as the outer ones : staminal column very slen-
der, over 3 lines in length; anthers spreading, about 2 lines long:
the six branches of the style with terminal capitellate stigmas. —
Collected by Mr. Pringle near Patzcuaro (unnumbered and not
distributed). The description of this attractive little species has
been drawn from specimens cultivated and kindly communicated
by Mr. Edward Gillett, of Southwick, Massachusetts.

Tradescantia angustifolia. A very slender grass-like spe-
cies, 6 inches in height : roots of numerous delicate fibres : stems
slender, glabrous, somewhat decumbent: leaves narrow, linear,
very acute, 1-2 inches long, a line or less in breadth, glabrous
except the ciliate margins of the sheaths: flowers small, about
3 lines in diameter, some solitaiy, but for the most part um-
bellately grouped at the ends of terminal peduncles (1-2 inches in
length): the subtending bracts much shorter than the pedicels:
sepals ovate, acute : petals roseate : stamens very different, the
longer ones with smooth bent filaments, the broadly dilated some-
what horseshoe-shaped connective bearing the small orange-colored
anther cells in a transverse position; in the shorter stamens the
anthers larger, pinkish, the connective much less developed, and the
cells parallel or nearly so : seeds triangular, brown, and somewhat
radially rugose. — Thin soil of limestone ledges, Las Canoas, San
Luis Potosi, August, 1891 (n. 3902).

186 PROCEEDINGS OF THE AMERICAN ACADEMY

XIII.

CONTRIBUTIONS FROM THE CHEMICAL LABORATORY
OF HARVARD COLLEGE.

OX CERTAIN PRODUCTS OF THE DRY DISTILLATION

OF WOOD: METHYLFURFUROL AND METHYL-

PYROMUCIC ACID.*

By Henry B. Hill and Walter L. Jennings.

Presented November 9, 1892.

Several years ago, one of us described f the occurrence of fur-
furol in not inconsiderable quantity among the products of the dry
distillation of wood at low and carefully regulated temperatures, as
carried on at Brooklyn under the direction of Dr. E. R. Squibb.
Although attempts were made at the time to separate by fractional
distillation the higher boiling constituents of the crude furfurol,
ordinary boiling flasks alone were employed, and the results were
so far from encouraging that a more thorough investigation was
for the moment relinquished. The gradual accumulation of larger
quantities of these higher-boiling oils encouraged us to renew the
investigation, and we soon found that fractions of constant boiling
point could readily be isolated by using in the distillation the ex-
tremely effective bead columns of Hempel.t The most noticeable
fraction which we obtained was one boiling at 184-186°. This
proved to contain chiefly methylfurfurol, a preliminary account of
which was published § soon after its identification. A few months
later Maquenne, || and Bieler and Tollens,^ quite independently of

* A part of the work described in the following paper was presented in the
form of a thesis to the Faculty of Arts and Sciences of Harvard University in
May, 1892, by Walter L. Jennings, then candidate for the degree of Doctor of
Philosophy.

t These Proceedings, XVI. 155.

f Zeitschrift anal. Chem., XX. 502.

§ Berichte der deutsch. chem. Gesellsch., XXII. 607.

|| Comptes Rendus, CIX. 571.

1 Berichte der deutsch. chem. Gesellsch., XXII. 3062 ; Ann. Chem. u. Pharm.,
CCLVII. 110.

OF ARTS AND SCIENCES. 187

each other, found the same methylfurfurol among the products
formed by the distillation of several species of seaweed with dilute
sulphuric acid, and showed that the fucusol of Stenhouse * was a
mixture of furfurol with this methylfurfurol. Shortly afterward
the same body was obtained by the action of dilute sulphuric acid
upon isodulcite by Maquenne,f who pointed out that this mode of
formation, taking into consideration the constitution of isodulcite
as established by Fischer and Tafel, t proved the methyl group to
be in the 8 position. This conclusion of Maquenne concerning the
structure of methylfurfurol was afterward confirmed in this Labo-
ratory by a study of the product formed by the action of aqueous
bromine upon methylpyromucic acid, and a brief description of
this reaction was published at the time.§ Instead of the half-
aldehyde of fumaric acid

/COOH
C2H<>

"xCOH

which is formed under like conditions from pyromucic acid, methyl-
pyromucic acid yields the acetacrjdic acid of Wolff, ||

GOOH

C2H2

x COCH3

and the formation of this ketone acid proves that the methyl group
is attached to the 8 carbon atom of the furfuran ring. We have
also studied the action of dry bromine upon methylpyromucic acid,
and have found that a somewhat unstable tetrabromide may be
prepared, although the substitution products are more readily ob-
tainable. For the preparation of the tetrabromide the temperature
must be kept below 0°; if the bromine be allowed to act at ordi-
nary temperatures a brommethylpyromucic acid is formed which
melts at 150-151°, and contains the bromine in the furfuran ring,
while at higher temperatures (50-60°) the bromine enters chiefly
the side chain and forms w-brommethylpyromucic acid melting at
117-148°. The formation of these two isomeric products at dif-
ferent temperatures recalls the analogous reactions in the aromatic
series, and the analogy is completely borne out by the behavior

* Ann. Chem. u. Pharm., LXXIV. 278. t Comptes Rendus, CIX. 603.

J Berichte der deutsch. chem. Gesellsch., XX. 1092 ; XXI. 2173.

§ Ibid., XXIII. 452.

|| Ibid., XX. 426; Ann. Chem. u. Pharm., CCLIV. 245.

188 PROCEEDINGS OF THE AMERICAN ACADEMY

of the two acids. We have also made a dibrommethylpyromucic
acid melting at 175°, in which one bromine atom is situated in the
furfuran ring, the other in the side-chain. By the action of water
upon the two acids which contain halogen in the side-chain we
have made the corresponding oxy-acids.

We had intended to make a thorough study of the higher boiling
fractions of the crude furfurol, and to determine as far as possible
the nature of the various constituents ; but the investigation of the
methylfurfurol and its derivatives proved so much more attractive
that we have contented ourselves with the partial examination of
the fractions boiling at 200-215° and established in them the pres-
ence of guaiacol.

Methylfurfukol.

The material which we had at our disposal was that portion of
the crude furfurol which remained behind at 175° on distilling the
oil several times from ordinary retorts or boiling flasks. It had
been accumulating for more than ten years, was dark in color,
somewhat thick and viscous, and left on distillation a large tarry
residue. We therefore distilled it from small copper retorts until
signs of decomposition appeared. While the earlier investigations
had shown that the temperature could be pushed to over 300°
without essential decomposition, we now found that carbonization
ensued at about 250°. At first we ascribed this difference in be-
havior to decomposition effected by long standing of the material;
but we subsequently learned that changes had also been made in
the mean time in the factory methods, and that it was quite possi-
ble that the greater part of our material had been subjected to the
newer treatment. A special examination of the residue yielded
by the distillation of nearly fifty kilograms of a fresh supply of
crude furfurol showed that in this case decomposition also set in
at 250°, so that no products boiling above this temperature could
be obtained.

On fractioning with the aid of a Hempel column the yellow dis-
tillate which was first obtained, we soon found that it still con-
tained considerable quantities of furfurol, and, aside from this, that
a comparatively large portion distilled between 180° and 185°,
and a smaller portion at 200-220°. As the distillation progressed,
the intermediate fractions diminished in such a way that it became
evident that but one body could be isolated between 165° and
200°, and that it boiled at a temperature not far from 185° (un-

OF ARTS AND SCIENCES. 189

corrected). We therefore continued the distillation, taking two-
degree fractions, and were ahle to collect a large portion which
boiled with satisfactory constancy at 184-186°. As the material
thus obtained showed the character of an aldehyde, a portion of it
was shaken with a concentrated solution of acid sodic sulphite.
The oil was almost wholly dissolved with the evolution of heat,
and as the solution cooled it solidified with the separation of flat
radiating prisms. These were drained thoroughly upon the pump,
washed with cold alcohol, pressed, and dried. The dry crystals
were then decomposed by the requisite amount of sodic carbonate
in aqueous solution, and the liberated aldehyde distilled over with
steam. The oil which passed over was then dried with fused
calcic chloride and distilled. It showed the constant boiling
point 187°, with the mercury column completely in vapor and
under a pressure of 766 mm. The boiling point of a second prep-
aration was found to be 186.5-187° under a pressure of 760 mm.
An analysis of the oil showed that its formula was C6H602.

0.1995 grm. substance gave 0.4788 grin. C02 and 0.0998 grm.
H20.

Calculated for C,;HG02. Found.

C 65.45 65.43

H 5.45 5.56

The formula of the substance, together with its strongly marked
resemblance to furfurol, identified it as a methylfurfurol, and by
oxidation with moist silver oxide it could readily be converted
into the corresponding methylp}rromucic acid.*

Freshly distilled methylfurfurol is a nearly colorless oil, with an
odor closely resembling that of furfurol. On standing it grows
dark-colored apparently more rapidly than furfurol, and acquires an
acid reaction. The compound which it forms with acid sodic sul-
phite crystallizes in flat concentrically grouped prisms, which are
usually rectangularly truncated. The salt dissolves in from two
to three parts of water at ordinary temperatures. In the pre-
liminary paper already referred to,f the statement was made that
methylfurfurol gave the characteristic color reaction with a solu-
tion of rosaniline decolorized by sulphurous acid. We have found,
however, that carefully purified meth}*lfurfurol gives to this solu-
tion but a slight brown-red, or, if added in larger quantity, but a
pale wine-red coloration, and are forced to conclude that the color

* See page 193. t Berichte der deutsch. chem. Gesellsch., XXII. 607.

190 PROCEEDINGS OF THE AMERICAN ACADEMY

formerly observed was due to a slight admixture of furfurol. It
gives, however, with diazobenzol sulphonic acid when tested in the
manner described by Penzoldt and Fischer * a color identical in
shade with that given by furfurol. With hydrochloric acid and
resorcine it gives an orange-red, with pyrogallol a carmine-red
condensation product. Aniline acetate paper gives at first no
color, or at best turns but a light yellow, but on standing a deep
orange-color is developed. With phenylbydrazine a liquid hydra-
zone is formed, which we have not further examined. Tbe specific
gravity of methylfurfurol we have found to be somewhat higher
than given by Maquenne.f A freshly prepared sample made with
great care gave us at 18° referred to water at the same temperature
the specific gravity 1.1087, or 1.1072 referred to water at 4°. As
the sample was slightly colored it was distilled twice in a stream
of hydrogen, but the specific gravity was altered but a few units
in the fifth decimal place. The original fraction 186-187° (cor.)
from which this sample was made gave a specific gravity of 1.1059.
Maquenne found the specific gravity of his fraction 185-187° to be
1.107, and of the portion boiling at 187° to be 1.101. In water
methylfurfurol is more sparingly soluble than furfurol, and re-
quires about thirty times its weight of water at ordinary tempera-
tures for complete solution.

Since it was difficult to form even an approximate estimate of
the relative amounts of furfurol and of methylfurfurol contained
in the crude oil from an examination of the residues from previous
distillations which we had at our disposal, we submitted to frac-
tional distillation about 50 kilograms of the crude oil. We used
a copper retort of eight litres' capacity, which was fitted with
a suitable column made out of large thin-walled brass pipe and
filled with glass beads. After repeated distillations we obtained
about two per cent of the material taken in the fraction boiling
from 182° to 186° (uncorrected), and sixty per cent in the fraction
boiling from 160° to 165°. Although the absolute amounts doubt-
less would have been somewhat increased by further separation of
the small intermediate fractions, the relative amounts could have
been little altered.

Methy If urfur amide, C18H18N203. — An aqueous solution of methyl-
furfurol, when mixed with amnionic hydrate, gives after the lapse

* Berichte der deutsch. chem. Gesellsch., XVI. 657.
t Ann. Chim. Phys., [6.], XXII. 84. -

OF ARTS AND SCIENCES. 191

of some time a crystalline precipitate of metliylfurfuramide. This
substance crystallizes in slender radiating needles, dissolves read-
ily in alcohol, ether, chloroform, benzol, or carbonic disulphide,
but is more sparingly soluble in ligroin. Tbe substance recrys-
tallized from ligroin was found to melt at 86-87°, and contained
the proper percentage of nitrogen.

0.3510 grm. substance gave 27.8 c.c. of moist nitrogen at 22° and
under a pressure of 759 mm.

Calculated for C18H18N,03 Found.

N 9.03 8.96

GUAIACOL.

The larger fractions of the oil boiling above methylfurfurol were
those which were collected between 200° and 220°, but even after
long continued distillation no substances of constant boiling point
could be isolated. While the oil did not appear to contain an alde-
hyde in sensible quantities, a large portion of it was soluble in
aqueous alkalies, and we thought it advisable to take advantage of
this fact in order to simplify our task. The fractions 200-215°
were therefore united, shaken with a solution of sodic hydrate, and
the aqueous emulsion distilled with steam as long as oil passed
over. The alkaline solution was then acidified and again distilled
with steam. The neutral oil when dried with calcic chloride dis-
tilled at 210-220°, and we have not yet examined it further. The
oil which was soluble in the alkaline solution boiled between 200°
and 205°, and the thermometer remained for a long time constant
at 202°. The physical properties of this oil and the emerald-green
color which ferric chloride developed in its alcoholic solution left
no doubt in our minds that it was guaiacol, and we thought that it
could possibly be most conveniently identified with precision by
converting it into the tribromguaiacol of Tiemann and Koppe.*
On adding bromine to an alcoholic solution according to their
directions, however, we obtained an unsatisfactory product. The
melting point, although somewhat higher than that given by Tie-
mann and Koppe (102°), was not sharp, and was little improved
by repeated recrystallization. As the inherent disadvantages in
adding bromine to an alcoholic solution were sufficiently obvious,
we substituted glacial acetic acid for the alcohol, and at once

* Berichte der deutsch. chem. Gesellsch., XIV. 2017.

c

Calculated for
C7H5Br302.

23.27

i.
23.25

Found
II.

H

1.39

1.65

Br

66.48

66.3

192 PROCEEDINGS OP THE AMERICAN ACADEMY

obtained a definite product. From 5 grams of our oil we obtained
8.3 grams of a highly crystalline, nearly colorless bromine derivative,
which melted at 111-112°, and a single recrystallization sufficed
to raise the melting-point to 115-116°. Further recrystallization
from alcohol or benzol failed to raise this melting-point. While
our product thus melted 14° higher than the tribromguaiacol of
Tiemann and Koppe, it agreed in other respects with their de-
scription, and the following analyses show that it had the same
composition : —

I. 0.2316 grm. substance gave 0.1974 grm. C02 and 0.0345
grm. H20.
II. 0.1603 grm. substance gave 0.2497 grm. AgBr.
III. 0.1705 grm. substance gave 0.2653 grm. AgBr.

in.

66.24

Since we had failed to identify our substance as guaiacol through
the melting point of this bromine derivative, we proceeded to pre-
pare from it pyrocatechin. For this purpose we used, instead of the
more usual hydriodic acid, hydrochloric acid, as W. H. Perkin, Jr.*
had recently shown the decomposition was in this case nearly per-
fect if the reaction took place in sealed tube at 170-180°. On
opening the tube, a gas escaped which burned with a green-bordered
flame. The aqueous solution was extracted with ether, and the
crystalline residue which was left upon evaporating the ether was
distilled. The substance boiled at 240-242°, and the solidified
distillate melted at 103-104°. When recrystallized from benzol it
formed colorless lustrous scales, which appeared under the micro-
scope to be rectangular plates, and melted sharply at 104°. The
boiling point of pyrocatechin is usually given at 240-245°, and the
melting point was found by Fittig and Mager f to be 104°. In
aqueous solution our product also gave with ferric chloride an em-
erald-green coloration which turned to a violet-red on the addition
of sodic, carbonate. It was thus established with precision that
pyrocatechin had been formed by heating with hydrochloric acid

* Journ. Chem. Soc, LVII. 589.

t Berichte der deutsch. chem. Gesellsch., VIII. 365.

OP ARTS AND SCIENCES. 193

the oil under investigation, and the latter was therefore in its turn
identified as guaiacol. It seems to us probable that the tribrom-
guaiacol, which we have just described, is identical with that of
Tiemann and Koppe, and that the low melting point which they
observed was due to by-products introduced by their method of
preparation. A more extended investigation of the matter was,
however, wholly foreign to our line of work. We hope that the
constituents of the crude furfurol which boil above 200° may be
studied more fully in this Laboratory at some future time.

Methylpyromucic Acid.

In order to prepare from methj-lf urfurol the corresponding methyl-
pyromucic acid, we first attempted to follow the methods which
we had already used in the manufacture of pyromucic acid from
furfurol. We found, however, that alkaline hydrates, either in
alcoholic or in aqueous solution,* gave us an extremely poor pro-
duct in very unsatisfactory quantity. Although the experiments
of Lessing in the laboratory of Limpricht f upon the oxidation of

* For many years a concentrated aqueous solution of sodic hydrate has been
used at this Laboratory in the preparation of pyromucic acid. Our method has
been, however, essentially different from that recommended by H. Schiff (Ann.
der Chem. u. Pharm., CCXXXIX. 374, CCLXI. 254), in that we have destroyed
the f urfuryl alcohol by hydrochloric acid instead of removing it with ether. The
saving of time and of ether has more than compensated us for the somewhat
diminished yield. 2 litres of furfurol are very gradually mixed with 1200 c.c.
of aqueous sodic hydrate (1 : 1), taking care by constant stirring and cooling
that the thick paste does not grow hot. On the following day 2 litres of con-
centrated hydrochloric acid are gradually added, the temperature toward the
end being allowed to rise somewhat to facilitate the complete decomposition of
the furfuryl alcohol. If the temperature rises too rapidly, the reaction becomes
violent. The furfuryl alcohol is in any case converted into a tough leathery
substance, which grows brittle on standing with the excess of hydrochloric acid.
The slightly colored mother liquor is drained off, the residue crushed in an iron
mortar, 4 litres of water added, and then calcic hydrate, until the solution is
permanently alkaline. After standing for several days, the solution being kept
slightly alkaline, the pyromucic acid is carried completely into solution. The
filtrate is but slightly colored, and this slight color may be almost wholly re-
moved by bone-black. The yield of nearly colorless pyromucic acid which
may be obtained in this way amounts to from 35 to 40 per cent of the weight
of furfurol taken.

t Ann. Chem. u. Pharm., CLXV. 279. Lessing obtained a weight of pyro-
mucic acid equal to but 14 per cent of the weight of furfurol employed, or but
12 per cent of the theoretical amount.
vol. xxvn. (n. s. xix.) 13

194 PROCEEDINGS OP THE AMERICAN ACADEMY

furfurol with argentic oxide, gave us little hope that we could in
this way conveniently prepare large quantities of methylpyromucic
acid, no hetter method suggested itself to us at the time, and we
were forced to adopt it. To our surprise, we found that we could
easily obtain in this way a weight of methylpyromucic acid which
nearly equalled that of the aldehyde taken, and that we could also
obtain from furfurol under the same conditions an equally satisfac-
tory yield of pyromucic acid. From methylfurfurol we obtained as
a maximum 84 per cent of the theoretical yield of methylpyromucic
acid, from furfurol 82 per cent of the calculated amount of acid.
As the weight of acid remaining in solution after precipitation
with hydrochloric acid was in neither case taken into account, the
reaction may fairly be called quantitative. The large yield which
we obtained was doubtless due in part to a slight modification of
the ordinary method of procedure, which we shall presently de-
scribe. Still we had no difficulty in obtaining from 10 grm. of fur-
furol in the usual way 8.5 grm. of argentic pyromucate, and from
the acidified mother liquor by extraction with ether 2.9 grm. of pyro-
mucic acid, so that the total yield of pyromucic acid in this case
was 7.25 grm., or 62.1 per cent of the theoretical amount. All the
methylpyromucic acid which we have used in our investigations we
have made by the following method. 10 grm. of methylfurfurol
were added to about 50 grm. of well washed argentic oxide sus-
pended in about 800 c.c. of hot water, and the whole heated quickly
to boiling. When the reaction appeared to be complete, pure
sodic carbonate was added in quantity sufficient to precipitate the
silver which had been carried into solution, and the feebly alkaline
solution again boiled. When the fresh well marked reduction which
then ensued was finished, the solution was filtered, evaporated to
small volume, again filtered, and acidified with hydrochloric acid.
The acid which separated as the solution cooled was nearly color-
less, and as a rule a single rec^stallization was sufficient to raise
the melting point to the proper point. The slight color could be
most conveniently removed, if necessary, by treating a solution of
the calcium salt with bone-black.

0.2007 grm. of the acid gave 0.4321 grm. C02 and 0.0900
grm. H20.

Calculated for C6H603. Found.

C 57.14 57.01

H 4.76 4.84

OP ARTS AND SCIENCES. 195

Methylpyromucic acid melts at 108-109°, and sublimes readily
at low temperatures. It is readily soluble in alcohol, ether, chlo-
roform, or hot benzol, more sparingly soluble in cold benzol, and
almost insoluble in carbonic disulphide. It is extremely soluble
in hot water, and on cooling it separates from concentrated solu-
tions in short, thick six-sided prisms, or in small six-sided plates
formed by the development of these prisms parallel to the basal
plane. From dilute solutions it frequently separates in feathery or
bladed aggregations. The solubility of the acid in cold water we
determined by titration with a standard solution of baric hydrate,
using phenolphthalein as an indicator.

I. 22.293 grm. of a solution saturated at 20° required for neu-
tralization 15.3 c.c. of a solution of baric hydrate, containing
0.01864 grm. Ba02H2 in 1 c.c.
II. 19.665 grm. of a solution saturated at 20° required for neu-
tralization 13.55 c.c. of the above solution of baric hydrate.

According to these determinations an aqueous solution saturated
at 20° contained the following percentages of acid: —

I. ii.

1.89 1.89

Methylpyromucic acid is therefore decidedly less soluble in
water at ordinary temperatures than pyromucic acid.*

For the further characterization of the acid we have prepared a
number of its salts.

Baric Methylpyromucate, Ba(C6H503)2. — This salt we made
by boiling an aqueous solution of the acid with baric carbonate.
The salt is readily soluble in cold water, somewhat less soluble in
hot water, and separates on evaporation in small colorless octahedral

* According to Houton Labillardiere (Ann. Chim. Phys., [2.], IX. 368), pyro-
mucic acid is soluble in 26 parts of water at 15°. This result is confirmed by
approximate determinations made in this Laboratory as a guide in the prepara-
tion of pyromucic acid. It was found that 100 c.c. of a solution saturated at
17° contained 3.35 grm. of the acid, and that 100 c.c. of a saturated solution of
sodic chloride at the same temperature dissolved 0.60 grm. of the acid. The
erroneous statement made in the preliminary description of the acid (Berichte
der deutsch. chem. Gesellsch., XXII. 608), that it was " somewhat more readily
soluble in water " than pyromucic acid, was based upon rough quantitative
results obtained in recrystallizing from water the small quantity of the acid
which I then had at my disposal. — H. B. H.

196 PROCEEDINGS OP THE AMERICAN ACADEMY

crystals which are anhydrous. The salt thoroughly dried by pres-
sure suffered no material loss of weight on exposure to the air.

I. 0.3366 grm. air-dried salt gave 0.2023 grm. BaS04.
II. 0.4261 grrn. air-dried salt gave 0.2562 grm. BaS04.

Calculated for Found.

Ba(C6H503)2. I. II.

Ba 35.40 35.34 35.34

The solubility of the salt in water at ordinary temperatures we
determined in the usual way.

I. 5.8353 grm. of a solution saturated at 19°. 6 gave 0.7950 grm.

BaS04.

II. 5.5326 grm. of a solution saturated at 19°. 6 gave 0.7526 grm.

BaS04.

According to these determinations the aqueous solution saturated
at 19°. 6 contained the following percentages of the salt: —

i. ii

22.62 22.59

In order to determine the solubility at higher temperatures we
followed essentially the method recommended by V. Meyer.*

I. 6.8590 grm. of a solution saturated at 99° gave 0.8655 grm.
BaS04.

II. 5.1805 grm. of a solution saturated at 99° gave 0.6480 grm.

BaS04.

The aqueous solution saturated at 99° therefore contained the
following percentages of the salt : —

i. ii.

20.95 20.78

Calcic Methylpyromucate, Ca(C6H503)2 . 2 H20. — The calcium
salt is readily soluble in cold water, and the solubility is slightly
increased by heat. It crystallizes in clusters of long radiating
needles which contain two molecules of water.

I. 0.3544 grm. air-dried salt gave 0.1475 grm. CaS04.

II. 0.3184 grm. air-dried salt gave 0.1333 grm. CaS04.

III. 0.8481 grm. air-dried salt lost at 110° 0.0931 grm. H20.

IV. 0.5421 grm. air-dried salt lost at 110° 0.0596 grm. H20.

* Berichte der deutsch. chem. Gesellsch., VIII. 1002.

OF ARTS AND SCIENCES. 197

Calculated for Found.

Ca(C6H503)2 . 2 H30. I. II. HI. IV.

Ca 12.28 12.24 12.31

H20 11.04 10.97 10.99

I. 0.2688 grm. salt dried at 110° gave 0.1254 grm. CaS04.
II. 0.3109 grm. salt dried at 110° gave 0.1452 grm. CaS04.

Calculated for

Found

Ca(C6H503)2.

I, II.

13.79

13.72 13.74

Ca

In determining the solubility of the salt, the calcium was precipi-
tated as oxalate and weighed as sulphate.

I. 6.8529 grm. of a solution saturated at 20°. 2 gave 0.4104 grm.
CaS04.
II. 7.8851 grm. of a solution saturated at 20°. 2 gave 0.4688 grm.
CaS04.

i. H.

12.77 12.68

Argentic Methylpyromucate, AgC6H503. — This salt may readily
be made by precipitation of a soluble salt with silver nitrate, and
may be recrystallized from hot water. It is sparingly soluble even
in boiling water, and crystallizes from aqueous solution in fine
slender needles.

I. 0.2110 grm. salt gave on ignition 0.0977 grm. Ag.
II. 0.4007 grm. salt gave on ignition 0.1855 grm. Ag.

Calculated for Found.

AgC6H503. I. II.

Ag 46.34 46.30 46.29

Sodic Methylpyromucate, NaC6H503. — The sodium salt is ex-
ceedingly soluble even in cold water. It separated from its solu-
tion in dilute alcohol after long standing in compact clusters of
small anhydrous needles.

I. 0.2752 grm. air-dried salt gave 0.1325 grm. Na2S04.
II. 0.4240 grm. air-dried salt gave 0.2034 grm. Na2S04.

Calculated for Found.

NaCcH503. I. II.

Na 15.53 15.60 15.53

Potassic Methylpyromucate, KCGH503. — The potassium salt is
also very readily soluble in cold water, and crystallizes in spherical
aggregations of short prisms, which appear to be anhydrous.

198 PROCEEDINGS OF THE AMERICAN ACADEMY

0.3385 grm. air-dried salt gave 0.1790 grm. K2S04.

Calculated for KC6H503. Found.

K 23.83 23.74

Ethyl Methyl pyromucate, C6H503C2H.5. — The ethyl ether of the
acid we made in the ordinary way by saturating a solution in an
equal weight of absolute alcohol with hydrochloric acid. The ex-
cess of hydrochloric acid was then driven off at a gentle heat, the
ether precipitated with water, washed with a dilute solution of
sodic carbonate, dried with calcic chloride and distilled. The
whole product passed over between 212° and 215°, and by far
the greater portion showed the constant boiling point 213-214°
with the mercury column completely in vapor under a pressure of
766 mm. The ether showed no tendency toward crystallization
when cooled with ice and salt.

I. 0.2363 grm. substance gave 0.5404 grm. C02 and 0.1392 grm.

H20.
II. 0.1570 grm. substance gave 0.3585 grm. C02 and 0.0921 grm.
H20.

Calculated for

Found.

C6H503C2HB.

I. II.

c

62.34

62.36 62.27

H

6.49

6.54 6.52

Methylpyromucamide, C6H502NH2. — Ethyl methylpyromucate
is readily attacked by concentrated aqueous ammonia, and the re-
action is completed in the cold after the lapse of two days. The
clear solution then yields on evaporation the corresponding amide
in long colorless prisms which melt at 131°. It is readily soluble
in alcohol, dissolves freely in hot benzol or ligroin, sparingly in
the cold, and may best be recrystallized from hot water, in which
it is readily soluble.

I. 0.2207 grm. substance gave 22.8 c.c. of moist nitrogen at 28°
and under a pressure of 762 mm.
II. 0.1839 grm. substance gave 19.1 c.c. of moist nitrogen at 26°
and under a pressure of 751 mm.

N

Calculated for

Found.

C6H502NH2.

I. II.

11.20

11.36 11.38

OF ARTS AND SCIENCES. 199

Action of Bromine and Water.

Although Maquenne* had shown that the ready formation of
methylfurfurol from isodulcite led directly to the conclusion that
it must contain its methyl group in the S position, it seemed
desirable to establish this point by independent facts. Since pyro-
mucic acid could readily be oxidized by bromine in aqueous solu-
tion, and converted into well marked bodies of the maleic acid
group, it seemed probable that methylpyromucic acid would also
yield analogous products. It was soon found that homogeneous
products could not easily be obtained by using an excess of bro-
mine, as is the case with pyromucic acid. Although a crystalline
derivative could be obtained under certain conditions, the yield
was not satisfactory, and viscous products were also formed. With
two molecules of bromine, however, it was easy to reach definite
results. Limpricht t showed in 1873 that pyromucic acid could
be converted into a body which he called the half-aldehyde of
fumaric acid by the action of two molecules of bromine upon
its aqueous solution, and v. Baeyer % subsequently proved that
fumaric acid could be formed from this by the action of argentic
oxide. It was evident, if methylpyromucic acid was decomposed
in an analogous fashion, that there should be formed either an
homologous aldehyde acid, or a ketone acid, according to the posi-
tion of the methyl group in the furfuran ring. The formation of
a ketone aldehyde under these conditions did not seem possible,
since Hill and Sanger § had shown that the aldehj-de group in
analogous reactions is invariably formed from the 8 carbon of the
pyromucic acid. The product formed from methylpyromucic acid
under these conditions proved to be a ketone acid, and a brief
description of the results of a preliminary examination which was
undertaken at the time by Mr. W. S. Hendrixson || and one of
us was published elsewhere about two years ago. For the sake of
completeness an account of these preliminary experiments will be
included in the description of our own work, and we also owe
to Mr. Hendrixson the analytical data which we publish. If
methylpyromucic acid is suspended in about fifteen times its

* Comptes Rendus, CIX. 603.

t Ann. der Chem. u. Pharm., CLXV. 285.

X Berichte der deutsch. chem. Gesellsch., X. 1362.

§ These Proceedings, XXI. 185.

|| Berichte der deutsch. chem. Gesellsch., XXIII. 452.

200 PROCEEDINGS OF THE AMERICAN ACADEMY

weight of cold water, and the vapor of bromine is slowly passed
in by means of a current of air, the color of the bromine is quickly
discharged, and the acid goes into solution with the escape of car-
bonic dioxide. When exactly two molecules of bromine have been
added, the whole is allowed to stand for a short time, and the col-
orless solution then thoroughly extracted with ether. The ether
left upon evaporation a crystalline body which was recrystallized
from boiling benzol, and finally from water. An analysis showed
that the formula of the substance was C5Hc03.

0.2461 grm. substance gave 0.4734 grm. C02 and 0.1185 grm.
H20.

Calculated for C6H603. Found.

C 52.64 52.47

H 5.26 5.35

The new body was readily soluble in hot water, more sparingly
soluble in cold water, and was acid in its character. It dissolved
readily in alcohol, ether, or boiling chloroform, more sparingly in
cold chloroform. In hot benzol it was quite readily soluble, and
very sparingly soluble in cold benzol, carbonic disulphide, or ligroin.
It crystallized in long slender lustrous needles, which melted at
122-123°. Recrystallization from various solvents failed to raise
the melting point, but after several careful sublimations it melted
at 123-124°. The formula of this acid was further controlled by
an analysis of its silver salt, which was prepared by the cautious
addition of ammonic hydrate to a solution of the acid containing
argentic nitrate. The salt can be recrystallized from boiling wa-
ter without difficulty, and forms concentrically clustered six-sided
plates.

I. 0.2237 grm. salt gave 0.1901 grm. AgBr.
II. 0.2926 grm. salt gave 0.2484 grm. AgBr.

Calculated for Found.

AgCBH503 I. II.

Ag 48.87 48.81 48.76

The acid which had thus been formed from methylpyromucic
acid corresponded well with the description of the acetacrylic acid
which Wolff * had shortly before made through the decomposition
of /3-bromlaevulinic acid. Its melting point, however, was given

* Berichte der deutsch. chem. Gesellsch., XX. 426.

OP ARTS AND SCIENCES. 201

by Wolff as 125-125°.5, although he adds in a more recent paper *
that impurities otherwise imperceptible may depress the melting
point from two to three degrees. In order to compare the two
acids, we have ourselves made the acetacrylic acid of Wolff from
/3-bromlaevulinic acid. In the preparation of the /3-bromlaevulinic
acid we followed with precision the directions of Wolff. The com-
plete purification of the crude acid was in our hands attended with
great loss of time and material, and, even after repeated recrystalli-
zation from carbonic disulphide, we failed to raise the melting
point above 58°, while Wolff gives 59° as the melting point of the
pure acid. Under these circumstances, we did not attempt to pre-
pare pure /3-bromlaevulinic acid in larger quantity, but decomposed
with sodic acetate in an acetic acid solution a preparation which
melted at 55-56°. The acetacrylic acid which we thus obtained
was to all appearance identical with that made from methylpyro-
mucic acid. As was to be expected, its melting point was some-
what low, 121-123°, but after several recrystallizations from benzol
melted at 123-124°. Wolff f describes the silver salt of his acid
as stellate needles, while the silver salt of our acid crystallized
in well formed six-sided plates. We convinced ourselves that the
same six-sided plates were formed by the addition of argentic
nitrate to a moderately concentrated solution of both acids, and
that on recrystallization these plates frequently formed dendritic
aggregations. These dendritic forms only were seen if an insuf-
ficiently purified acid was used. While it is very possible that the
acids which we had in our hands were in neither case absolutely
pure, we cannot doubt the identity of the material from the two
sources.

In order to identify still further our product with Wolff 's acet-
acrylic acid, we dissolved it in chloroform and added at low tem-
perature one molecule of bromine. The color of the bromine was
discharged, and on evaporation a crystalline residue was obtained
which melted after recrystallization from a mixture of benzol and
carbonic disulphide at 107-108°. According to Wolff f the a/3-di-
bromlaevulinic acid melts at this point. With phenylhydrazine
our product also readily gave the corresponding hydrazone, identical
in every respect with the body described by Bender % and shortly

* Ann. Chem. u. Pharm., CCLXIV. 245.

t Ibid., p. 248.

t Berichte der deutsch. chem. Gesellsch., XXI. 2494.

202 PROCEEDINGS OF THE AMERICAN ACADEMY

afterward by Decker.* It crystallized in small yellow prisms,
which melted at 156-157°, and dissolved in concentrated sulphuric
acid with a red color. Analysis showed that it had the formula
C11H12N202.

I. 0.2240 grin, substance gave 0.5299 grin. C02 and 0.1190 grin.
H20.
II. 0.2173 grm. substance gave 26.6 c.c. of moist nitrogen at 23°
and under a pressure of 752 mm.

Calculated for Found.

CnH12N202. I. n.

C 64.71 64.52

H 5.88 5.90

N 13.73 13.64

Bromine in aqueous solution, therefore, converts methylpyro-
mucic acid into acetacrylic acid according to the equation

C6H603 + 2 Br2 + 2 H20 = C5H603 + C02 + 4 HBr.

The formation of this ketone acid from methylpyromucic acid,
while pyromucic acid under the same conditions yields an aldehyde
acid, shows conclusively that the methyl group of the methylpyro-
mucic acid stands in the 8 place.

Action of Concentrated Sulphuric Acid.

We have thought that it might be possible to bring additional
evidence as to the structure of the methylpyromucic acid through
an investigation of the sulphonic acid derived from it. A study of
the sulphonic acids derived from pyromucic acid had already shown
that 5-sulphonic acids were always formed by the action of fuming
sulphuric acid, whenever the b hydrogen had not already been other-
wise replaced; when the 8 hydrogen had been thus replaced, /3-sul-
phonic acids were formed. Moreover it was very easy to distinguish
between the two isomers in that bromine in aqueous solution in-
stantly formed sulphuric acid from the 8-sulphonic acids, while the
/3-sulnhonic acids were oxidized to products which retained the sul-
pho group. Methylpyromucic acid was added with careful cooling
to three times its weight of fuming sulphuric acid, the whole
allowed to stand for twenty-four hours, and the diluted solution
then neutralized with baric carbonate as usual. The barium salt
which was obtained by evaporating the filtered solution crystallized

* Berichte der deutsch. chem. Gesellsch., XXI. 2937.

OF ARTS AND SCIENCES. 203

in long needles, which were frequently collected in globular aggre
gatioDs. The salt was hardly more soluble in hot than in cold
water, and could best be obtained by the evaporation of its cold
aqueous solution in vacuo over sulphuric acid. In this respect it
closely resembled the baric /3-sulphopyromucate. An anatysis
showed that the salt was baric sulphomethylpyromucate, and that it
contained five molecules of water of crystallization.

I. 0.4798 grm. air-dried salt gave 0.2597 grm. BaS04.
II. 0.6078 grm. air-dried salt lost at 165° 0.1383 grm. H20.

Calculated for Found.

BaCcH4S06 5H20. I. II.

Ba 31.78 31.83

H20 20.87 20.71

0.5272 grm. salt dried at 165° gave 0.3598 grm. BaS04.

Calculated for Ba C6H4S06. Found.

Ba 40.17 40.13

Bromine water gave in an aqueous solution of the salt no precipi-
tate even on boiling, but after this treatment with bromine, if baric
hydrate was added to alkaline reaction a white flocculent precipitate,
which closely resembled baric sulphofumarate, appeared. This be-
havior showed conclusively that the sulpho group had not entered
the furfuran ring in the 8 position, and the conclusion seems war-
ranted that it had not done so only because the methyl group
already occupied that place.

Brommethylpyromucic Acids.

Bromine acts readily upon methylpyromucic acid at ordinary
temperatures, and substitution is so easily effected that the isola-
tion of an addition product is a matter of considerable difficulty.
The instability of the addition product renders it unsuitable for
the preparation of substituted acids, and facilitates the formation of
satisfactory products by direct substitution. The nature of the
products thus formed is, however, largely dependent upon the tem-
perature at which the reaction takes place. At low temperatures
the bromine enters first the furfuran ring and afterwards the methyl
group, while at higher temperatures the methyl group is first attacked,
altbough substitution apparently takes place at the same time to a
certain extent in the ring. The facts which we have here observed
evidently correspond precisely with those so thoroughly established

204 PROCEEDINGS OF THE AMERICAN ACADEMY

in the aromatic series. Moreover, those hodies which contain the
halogen in the side-chain are extremely susceptible to double de-
composition, and are even decomposed by heating for a short time
with water. The halogen in the main ring, on the other hand, is
held quite as persistently as that in the corresponding derivatives
of pyromucic acid. The study of these bodies presented at first
many difficulties, the solution of which cost us so much time and
labor that we have been unable to carry our researches as far as we
had hoped. Since one of us must now relinquish the work, we
shall present the results we have obtained, although they are in
many respects incomplete. Further researches upon the subject
will be made in this Laboratory. We are especially sorry that we
have been unable to determine with precision the place in which
the bromine enters the furfuran ring ; while we have obtained by
oxidation of the brommethylpyromucic acid in question an acid
which is doubtless a bromacetacrylic acid, we have not yet been able
to establish its structure and thus make it available in determining
the constitution of the brommethylpyromucic acid from which it is
formed. There can be little doubt, however, that the bromine in
this case enters the /3 position, as it does with pyromucic acid it-
self as soon as the 8 hydrogen atom is replaced by bromine.

/3(?)-Brommethylpyromucic Acid.

When dry bromine acts at ordinary temperatures upon methyl-
pyromucic acid, hydrobromic acid is at once evolved, and brom-
methylpyromucic acid is formed. The reaction is most readily
controlled by the use of a solvent, and we have found glacial acetic
acid most convenient for the purpose. We have found it necessary
to add decidedly more than one molecule of bromine, and the best
results were obtained by using three atoms. The methylpyromucic
acid is dissolved in one and a half times its weight of glacial acetic
acid (99.5 per cent), and the necessary amount of bromine care-
fully added, taking care that the temperature does not rise above
17°. After standing for some time at ordinary temperatures, the
greater part of the hydrobromic acid is expelled in vacuo over
lime, the residue poured into water, and the acid extracted with
ether. The crude acid left on the distillation of the ether we have
found it most advantageous to convert into the sodium salt with
alcoholic sodic hydrate. The sodium salt is easily collected
upon a filter, and the acid is then reprecipitated from its aqueous

OF ARTS AND SCIENCES. 205

solution after decolorization with bone-black. The acid may be
further purified by several repetitions of the same process.

I. 0.2279 grm. substance gave 0.2935 grm. C02 and 0.0526 grm.
H20.
II. 0.1147 grm. substance gave 0.1055 grm. AgBr.

Calculated for

Found.

C6H5Br02.

I. II.

c

35.12

35.13

H

2.44

2.56

Br

39.02

39.1

Brommethylpyromucic acid crj'stallizes in colorless branching
needles, which melt at 150-151°. It is readily soluble in alcohol,
ether, or chloroform, somewhat sparingly soluble in cold, more
readily in hot benzol. In carbonic disulphide or ligroin it dis-
solves but sparingly even on boiling. It is somewhat sparingly
soluble in hot water, and is deposited in clusters of branching
needles as the solution cools. The solubility of the acid in water
at ordinary temperatures we determined in the usual way. We
neutralized with baric carbonate the solution of the acid, and deter-
mined as sulphate the barium which had been dissolved.

I. 17.598 grm. of a solution saturated at 21°. 4 gave 0.0271 grm.
BaS02.
II. 16.031 grm. of a solution saturated at 21°. 4 gave 0.0264 grm.
BaS04.

The aqueous solution saturated at 21°. 4 therefore contained the
following percentages of the acid: —

i. ii.

0.27 0.29

For the further characterization of the acid we also prepared cer-
tain of its salts.

Baric Brommethylpyromucate, Ba(C6H4Br03)2 • 4 H20. — This
salt may readily be made from a solution of the ammonium salt by
precipitation. It is sparingly soluble in cold water, more readily
soluble in hot water, and crystallizes from the hot aqueous solution
on cooling in dendritic needles, which contain four molecules of
water. The salt is permanent in the air, but effloresces rapidly over
sulphuric acid.

206 PROCEEDINGS OF THE AMERICAN ACADEMY

I. 0.4478 grm. air-dried salt gave 0.1690 grm. BaS04.
II. 0.8747 grm. air-dried salt lost at 110° 0.1030 grm. H20.

Calculated for Found.

Ba(C6H4Br03)2 . 4 H20. I. II.

Ba 22.20 22.19

H20 11.67 11.78

0.3664 grm. salt dried at 110° gave 0.1558 grm. BaS04.

Calculated for Ba(C6H4Br03)2. Found.

Ba 25.14 25.00

The solubility of the salt in cold water was determined in the
usual way.

I. 19.211 grm. of a solution saturated at 20°. 2 gave 0.0518 grm.

BaS04.

II. 19.984 grm. of a solution saturated at 20°. 2 gave 0.0466 grm.
BaS04.

The aqueous solution saturated at 20°. 2 therefore contained the
following percentages of the anhydrous salt : —

i. ii.

0.63 0.55

Calcic Brommethylpyromucate, Ca(C6H4Br03)2 . 3 H20. — The cal-
cium salt we prepared by precipitating with calcic chloride an
ammoniacal solution of the acid. It crystallized from hot water in
clusters of short needles which contained three molecules of water.
The salt was permanent in the air, and lost but little in weight
over sulphuric acid.

I. 0.2508 grm. air-dried salt gave 0.0680 grm. CaS04.
II. 0 5443 grm. air-dried salt lost at 110° 0.0584 grm. H20.

Calculated for Found.

Ca(C6H4Br03), . 3 H20. I. II.

Ca 7.97 7.98

H20 10.76 10.73

0.2724 grm. salt dried at 110° gave 0.0584 grm. CaS04.

Calculated for Ca(C0H4BrO3)2. Found.

Ca 8.93 8.86

In determining the solubility of the salt the calcium was precipi-
tated as oxalate, and converted into sulphate before weighing.

OF ARTS AND SCIENCES. 207

I. 15.373 grm. of a solution saturated at 20° gave 0.0189 grm.
CaS04.
II. 13.879 grin, of a solution saturated at 20° gave 0.0170 grm.
CaS04.

The aqueous solution saturated at 20° therefore contained the
following percentages of the anhydrous salt: —

I. II.

0.41 0.10

Argentic Brommethylpyromucate, AgC6H4Br03. — The silver salt
crystallizes from hot water in spherical aggregations of dendritic
needles.

0.0956 grm. salt gave 0.0574 grm. AgBr

Calculated for AgCGH4Br03. Found.

Ag 34.61 34.48

Potassic Brommethylpyromucate, KC6H4Br03. — This salt is
very readily soluble even in cold water, and crystallizes on slow
evaporation of its aqueous solution in small anhydrous needles.

0.2789 grm. salt gave 0.0993 grm. K2S04.

Calculated for KCcH4Br03. Found.

K 16.08 15.99

Action of Bromine and Water.

The whole behavior of the brommethylpyromucic acid showed
conclusively that its bromine atom was situated in the furfuran
ring. Although the bromacetacrylic acids had not yet been made,
one of which would doubtless be formed by the oxidation of this
brommethylpyromucic acid, and we therefore could not hope to de-
termine whether the bromine was in the /3 or in the y position,
we nevertheless thought it best to investigate the products of oxi-
dation. Brommethylpyromucic acid was suspended in thirty times
its weight of water, and somewhat more than two molecules of
bromine then slowly passed in by means of a current of air. The
acid was readily carried into solution, and at the same time a small
amount of an insoluble substance was formed. The filtered solu-
tion was extracted with ether, and the ethereal extract dried with
calcic chloride. The viscous residue which was left on the distilla-
tion of the ether gradually solidified on standing over sulphuric
acid in vacuo. This body proved to be an acid, containing bromine,

208 PROCEEDINGS OP THE AMERICAN ACADEMY

readily soluble in water, but crystallizing from benzol by evapora-
tion in rosettes. The melting point of the recrystallized acid was
found to be 61°. An analysis showed that the percentage of
bromine contained in this acid agreed with that required by a
bromacetacrylic acid.

0.1630 grm. substance gave 0.1594 grm. AgBr.

Calculated for C5H5Br03. Found.

Br 41.45 41.62

The oxidation had therefore taken precisely the same direction
as that followed by the analogous decomposition of methyl pyro-
mucic acid, and through this product of oxidation it will doubtless
be possible at some future time to fix the constitution of the brom-
methylpyromucic acid. A product apparently identical with this
we have also obtained by the action of dilute nitric acid.

The insoluble product formed at the same time with the brom-
acetacrylic acid we unfortunately have not been able to study fur-
ther. It is not acid in its character, contains a large amount of
bromine, and crystallizes from benzol in long colorless prisms,
which melt at 90-91°.

<»-Brommethylpyromucic Acid.

Although bromine in acting upon methylpyromucic acid at ordi-
nary temperatures enters at once the furfuran ring, at the tempera-
ture of boiling carbonic disulphide or chloroform it attacks chiefly
the methyl group, and a bromine derivative is formed in consider-
able quantity which differs wholly in its properties from the acid
just described. The reaction is not perfectly simple, for we have
found that we could obtain the best yield of the new product by
using twice the theoretical quantity of bromine. We have dis-
solved the methylpyromucic acid in six times its weight of chloro-
form and slowly added to the boiling solution two molecules of
bromine diluted with its own weight of chloroform. The evolu-
tion of hydrobromic acid at once begins, and frequently before the
bromine is all added a heavy crystalline body separates from the
hot solution. When the reaction is over, the chloroform is well
cooled, the crystalline product, which amounts to about sixty per
cent of the weight of methylpyromucic acid taken, filtered off, and
washed with cold chloroform. It may then be recrystallized from
boiling chloroform or benzol.

Calculated for

C6H5Br03.

c

35.12

H

2.44

OF ARTS AND SCIENCES. 209

I. 0.2152 grin, substance gave 0.2758 grin. C02 and 0.0490 grm.
H20.
II. 0.1176 grm. substance gave 0.1079 grin. AgBr.

Found.
I. II.

34.95
2.53
Br 39.02 39.04

Tbe a-brommethylpyromucic acid crystallizes in small clustered
oblique plates which melt at 147-148°. It is readily soluble in
alcohol, ether, glacial acetic acid, or acetone, somewhat sparingly
soluble in boiling benzol or chloroform, from which solvents it
crystallizes well on cooling. In boiling toluol it is freely soluble,
sparingly soluble in the cold, and almost insoluble in carbonic di-
sulphide. It is but slowly acted on by cold water, but on warming
it is readily dissolved with decomposition. The solution contains
hydrobromic acid in abundance, and upon evaporation a crystalline
acid is obtained, which is free from bromine. This behavior, which
is in such striking contrast with the extreme stability of the de-
rivatives of pyromucic acid that contain halogen, sufficiently estab-
lishes the position of the bromine in the side-chain. It also
effectually prevented the preparation of its salts by the ordinary
methods.

Decomposition by Water.

The product formed by the action of water upon a>-brommethyl-
pymmucic acid we have studied a little more in detail. After
heating an aqueous solution for some time at 100° it was evaporated
over lime in vacuo. The hard black crystalline residue was dis-
solved in hot water, filtered from the separated carbon, and again
evaporated. The brownish vitreous crystalline mass thus obtained
melted with decomposition at 158-162°, and by recrystallization
from a mixture of toluol and absolute alcohol the melting point
could be raised to 162-163°, although the body still melted with
decomposition. A combustion showed that the substance was w-
oxymethylpyromucic acid.

0.2623 grm. substance gave 0.4870 grm. C02 and 0.1052 grm.
H20.

Calculated for C6H604. Found.

C 50.70 50.63

H 4.23 4.46

VOL. XXVII. (n. S. XIX ) 14

210 PROCEEDINGS OP THE AMERICAN ACADEMY

cu-Oxymethylpyroniucic acid is readily soluble in water, alcohol,
or glacial acetic acid. In ether it is but slightly soluble, and in
benzol, toluol, chloroform, or carbonic disulphide it is almost wholly
insoluble. The barium salt of the acid is readily soluble in water,
and is left as a varnish as its aqueous solution evaporates. From
concentrated solutions it is thrown down as a flocculent precipitate
on the addition of alcohol. We have not yet examined it further,
and we have as yet found no other salts of a more inviting character.

The ease with which the w-brommethylpyromucic acid entered
into reaction with water naturally suggested the study of its be-
havior with other reagents. Unfortunately, we were unable to
pursue our investigations in this direction, but further researches
will be made in this Laboratory.

In the preparation of the w-brommethylpyromucic acid small
quantities of the isomeric acid were also apparently formed. From
the chloroform mother liquors we obtained, after treatment with
water and baric carbonate, a small amount of a crystalline acid
which melted at 149-151°, and in other respects resembled the
brommethylpyromucic acid first described.

Wj3( ?)-DlBROMMETHYLPYROMUCIC AdD.

If the brommethylpyromucic acid melting at 150-151° is treated
with bromine in boiling chloroform, a second atom of bromine
enters the side-chain and a dibrommethylpyromucic acid is formed.
The acid which separates on cooling or after partial evaporation of
the solvent is washed with cold chloroform, and recrystallized from
boiling toluol. This acid may perhaps more economically be made
by the direct action of bromine at ordinary temperatures. Methyl-
pyromucic acid is exposed over night to the vapor of three times its
weight of bromine. The semiliquid product is well washed with
carbonic disulphide, next with chloroform, and the dry crystalline
residue recrystallized from boiling toluol. Our analyses are not
altogether satisfactory, but they leave no doubt as to the nature of
the body.

I. 0.2877 grm. substance gave 0.2735 grm. C02 and 0.0418 grm.

H20.
II. 0.2086 grm. substance gave 0.2748 grm. AgBr.

Found.
I. II.

25.92
1.61

56.07

c

Calculated for
CnH4Br,Os.

25.35

H

1.41

Br

56.33

OF ARTS AND SCIENCES. 211

This dibrominethylpyromucic acid crystallizes in small oblique
tabular crystals, which melt at 175° with decomposition. It is
readily soluble iu alcohol, ether, or glacial acetic acid, is but spar-
ingly soluble in boiling benzol or chloroform, and almost insoluble
in carbonic disulphide or ligroin. In boiling toluol it is quite
readily soluble.

Action of Water.

On warming with water the acid is decomposed, hydrobromic
acid is formed, and the solution then contains an oxybrominethyl-
pyromucic acid. We prepared this acid first by treating with
water the product formed by the vapors of bromine upon methyl-
pyromucic acid, and separating it from the brommethylpyromucic
acid melting at 151° which accompanied it by washing the mixed
acids with benzol. The acid thus prepared from the crude material
was absolutely identical with that afterwards made from the pure
dibrommethylpyromucic acid. For analysis the substance was
crystallized from a mixture of benzol and alcohol.

I. 0.1950 grm. substance gave 0.2333 grm. C02 and 0.0420 grm.

H20.
II. 0.1695 grm. substance gave 0.1445 grm. AgBr.

Found.

n.

c

Calculated for
CcH5Br04.

32.58

i.
32.63

H
Br

2.26
36.20

2.39

36.28

The o>-oxy-£(?) -brommethylpyromucic acid is readily soluble in
alcohol and ether, very sparingly soluble in boiling carbonic disul-
phide, somewhat more readily soluble in boiling chloroform, from
which it separates on cooling in obliquely terminated prisms. It
is sparingly soluble in hot benzol, and almost insoluble in ligroin.
It is readily soluble in hot water, more sparingly in cold, and
separates from dilute aqueous solutions in large obliquely termi-
nated prisms, which contain one molecule of water. The crystals
effloresce slowly over sulphuric acid, or even in the air after months
of exposure, but we were unable to dehydrate them by heat without
bringing about slight decomposition.

I. 0.4413 grm. of acid cr3Tstallized from water lost over sulphuric

acid 0.0328 grm. H20.
II. 0.2117 grm. of acid dried in desiccator over night gave
0.1681 grm. AgBr.

212 PROCEEDINGS OP THE AMERICAN ACADEMY

Calculated for

Found.

C6H5Br04 . H20.

I. II.

H20

7.53

7.43

Br

33.47

33. £

The anhydrous acid melts at 153-154°, and on cooling forms a
viscous gummy mass. Sodium amalgam reduces the acid without
difficulty, and yields the w-oxymethylpyromucic acid already
described. The barium salt of the acid is readily soluble in water,
and crystallizes in clustered short needles, but we have made no
further study of its salts.

Methylpyromucic Tetrabromide.

We have already spoken of the instability of the addition pro-
duct which methylpyromucic acid forms with bromine. We suc-
ceeded in isolating it by adding two molecules of bromine diluted
with a little chloroform to a solution of methylpyromucic acid in
five times its weight of chloroform well cooled with ice and salt.
The bromine was slowly added with constant shaking, and at this
low temperature but little hydrobromic acid was noticed. The ad-
dition product soon began to separate in flat colorless needles, which
were frequently twinned at right angles. After the bromine had
all been added, the whole was allowed to stand for a short time, and
the product then quickly filtered upon the pump and washed with
cold chloroform. It was then pressed with filter paper and dried
in desiccator. As we fouud it impossible to recrystallize the sub-
stance without serious decomposition, we analyzed it without fur-
ther purification. On exposure to moist air it rapidly liquefied,
and even over sulphuric acid it soon evolved hydrobromic acid in
abundance. Analyses IV. and V., made with material which had
stood for two and four days respectively in desiccator, show how
rapidly the decomposition progresses.

I. 0.2695 grm. substance gave 0.1668 grm. C02 and 0.0383
grm. H20.
II. 0.3509 grm. substance gave 0.2182 grm. C02 and 0.0467
grm. H20.

III. 0.2011 grm. substance freshly made gave 0.3393 grm. AgBr.

IV. 0.1564 grm. of same substance after two days gave 0.2601

grm. AgBr.
V. 0.1520 grm. of same substance after four days gave 0.2513
grm. AgBr.

OP ARTS AND SCIENCES. 213

Calculated for

Found.

C6H6Br403.

i

ii.

III.

c

16.14

16.88

16.96

H

1.35

1.58

1.48

Br

71.74

71.81

IV.

70.79 70.37

Methylpyromucic tetrabromide is very sparingly soluble in car-
bonic disulpbide or ligroin, somewbat less sparingly soluble in
cbloroform or benzol. In hot chloroform or benzol it dissolves
more freely, but decomposition evidently ensues, for little unaltered
substance crystallizes on cooling. The substance melts at about
95° with decomposition, but the melting point varies with the
rapidity with which it is heated. Although the addition product
is so unstable we have been able to find but few definite products
resulting from its decomposition. Alcoholic sodic Irydrate appar-
ently destroys it completely. Sodic acetate in glacial acetic acid
gives the brommethylpyromucic acid melting at 150-151°, and the
same acid also appears to be formed in the spontaneous decomposi-
tion of the body when exposed to the air.

Further investigations in this direction will be made in this
Laboratory.

214 PROCEEDINGS OF THE AMERICAN ACADEMY

XIV.

CONTRIBUTIONS FROM THE CHEMICAL LABORATORY
OF HARVARD COLLEGE.

ON CERTAIN DERIVATIVES OF PYROMUCAMIDE.

By Charles E. Saunders.

Presented by Henry B. Hill, November 9, 1892.

This investigation was undertaken at the suggestion of Professor
H. B. Hill, in the hope of obtaining from pyromucamide or its deriv-
atives, through Hofmann's * reaction, an amine having the nitrogen
atom directly united to a carbon atom of the furfuran ring, no such
amine being at present known. Since preliminary experiments
with pyromucamide had shown that the reaction was complicated
by products formed through the action of the bromine upon the
furfuran group, 08-dibrompyromucamide was chosen as better
adapted to the purpose, since the corresponding acid is unaffected
by bromine. In this case, however, the product proved to be the
nitrile of the acid, instead of the amine, with one less carbon atom.
The behavior of pyromucamide with dry bromine was next studied,
and a stable tetrabromide isolated, and at the same time the action
of bromine in aqueous solution upon pyromucamide was examined
in order to find an explanation of certain striking color reactions
which had previously been observed in this Laboratory.

The Action of Bromine and Potassium Hydroxide on
/38-Dibro mpyromuca m ide .

Bromine alone has no marked action on /3S-dibrompyromucamide,
the amide dissolving quietly in the bromine. On evaporating, the
amide can be recovered unchanged, though the removal of the last
portions of bromine at ordinary temperatures occupies considerable
time, indicating perhaps the production of an unstable tetrabro-

* Berichte der deutsch. chera. Gesellsch., XIV 2725; XV. 407, 752, 762;
XVII. 1406, 1923 ; XVIII. 2734.

OF ARTS AND SCIENCES. 215

mide. Nevertheless, all attempts to prove more definitely the for-
mation of such a product failed. When the amide was dissolved
in bromine and the solution treated with aqueous potassium hy-
droxide, a small yield of a substance insoluble in water was
obtained. This was filtered off, washed with water, and distilled
with steam. The best yield was obtained as follows. One part
of the amide was dissolved in 1.8 parts of bromine (about six
atoms of bromine to one molecule of amide) in a large beaker.
Over this solution was poured a considerable quantity of a cold
five per cent solution of sodium or potassium hydroxide. The
contents of the beaker were kept cold, and allowed to stand, the
alkaline reaction being maintained by the occasional addition of a
small portion of 20 per cent sodium hydroxide solution. The
insoluble product gradually rose to the surface, as the bromine
disappeared, and was skimmed off. It was washed with dilute
acid, and then distilled with steam. The yield was nearly 13 per
cent of the weight of amide taken. For further purification the
substance was crystallized from a very small quantity of alcohol,
solution being brought about at 90° to 100° under pressure.
The substance gave the following results on analysis : —

I. 0.4259 grm. substance gave 0.3745 grm. C02 and 0.0160 grm.
H20.
II. 0.2044 grm. substance gave 0.3082 grm. Ag.Br.
III. 0.2056 grm. substance gave 10.3 c. c. of moist nitrogen at 15°. 3
and 757.5 mm. pressure.

in.

Calculated for

Found.

C5HBr2NO.

i.

II.

c

23.90

23.98

H

0.40

0.42

Br

63.75

64.17

N

5.58

5.84

The analysis shows that the substance is not the expected amine,
but is /?S-dibromfurfuronitrile. This conclusion was confirmed
by the reactions of the substance, and by its preparation through
the dehydration of the amide, using phosphorus pentachloride as
the dehydrating agent. The amide was mixed with the calculated
quantity of phosphorus pentachloride, and the mixture heated in
a distilling flask to about 200°, until hydrochloric acid ceased to
be given off. The contents of the flask were then distilled with
steam. The yield of dibromfurfuronitrile was 56 per cent of the

216 PROCEEDINGS OP THE AMERICAN ACADEMY

calculated amount. The substance as thus obtained was found to
be identical in composition and physical properties with that
formed by the action of bromine and dilute potassium hydroxide
on the dibromamide. A combustion of this product gave the
following results : —

0.4272 grm. substance gave 0.3793 grm. C02 and 0.0217 grm.
H20.

Calculated for C5HBr2NO. Found.

C 23.90 24.21

H 0.40 0.56

Properties of fiS-Dibromfitrfuronitrile. — It is a colorless solid,
possessing a characteristic and rather pleasant odor. It is volatile
with steam, scarcely at all soluble in water, readily soluble in ether
and in hot alcohol (especially at 100° under pressure). Its melting
point is 88° (uncor.), and its boiling point 225° (uncor.). It can
be sublimed. It crystallizes from superheated alcohol in leaflets or
plates. On standing for several days in a warm room with concen-
trated hydrochloric acid, it is converted into /?S-dibrompyromuca-
mide. When it is heated for about an hour in a sealed tube at
100° with concentrated hydrochloric acid, a considerable amount
of /38-dibrompyromucic acid is formed. Prolonged heating causes
blackening.

These two reactions were tried with the nitrile prepared in both
ways. In alcoholic solution sodium amalgam formed no reduction
product. The nitrile was dissolved in dilute alcohol, and treated
with two per cent sodium amalgam, a current of carbon dioxide
being passed through until the action was over. The distillate
obtained from this was not alkaline, and gave practically no resi-
due when acidified and evaporated. The residue in the flask gave,
on evaporation, needles of /38-dibrompyromucamide.

When the solution of dibromamide in bromine was treated with
dilute cold potassium or sodium hydroxide, the only product found,
beside the nitrile, was monobrommaleic acid. This was identified
by its melting point and other physical properties, as well as those
of its barium salt.

The dehydration of the dibromamide, — under the conditions of
the experiments related, — with formation of the nitrile, is par-
ticularly interesting, because Hofmann * found that, in preparing

* Berichte der deutsch. chem. Gesellsch., XVII. 1406, 1920.

OP ARTS AND SCIENCES. 217

amines from amides by the method introduced by him, nitriles
were sometimes produced, chiefly when working with the amides
of the higher fatty acids; but the nitriles thus formed always con-
tained one carbon atom less than the amide with which he started,
and he considers the amine to be an intermediate product in these
cases. In the present instance, however, since the nitrile contains
the same number of carbon atoms as the amide, this interpretation
of the reaction cannot be applied. The author has no explana-
tion to offer. It is worthy of note that the same reaction takes
place, whether the alkali used is potassium, sodium, or barium
hydroxide.

The Action of Bromine on Pyromucamide.

The tetrabromide of pyromucamide is obtained by dropping
small portions of powdered pyromucamide into bromine kept cooled
below zero. One should use 3.6 parts of bromine to one part of
pyromucamide; that is, about five atoms of bromine to one mole-
cule of pyromucamide. The liquid becomes thick and should be
well stirred. After the pyromucamide has all been added, the
excess of bromine is allowed to evaporate, and cold alcohol poured
over the well cooled residue. On standing, a pale yellow, finely
divided solid is separated from the dark mass. After the latter
has been completely broken up, the product is filtered off and
washed with ether. The yield is between 50 and 60 per cent of
the calculated amount. For further purification the substance is
dissolved in ethyl acetate or acetone, and the greater part of the sol-
vent distilled off. It is then filtered, and washed again with ether.
The substance is thus obtained in minute, colorless, glistening
crystals. An analysis gave the following results : —

I. 0.3417 grm. substance gave 0.1751 grm. C02 and 0.0410 grm.

H20.
II. 0.1110 grm. substance gave 0.1950 grm. AgBr.
III. 0.4586 grm. substance gave 13.6 c.c. of moist nitrogen at
23°. 5 and 765 mm. pressure.

Calculated for Found.

CfiH6NBr40,. I. II. III.

13.92 13.98

H 1.16 1.33

Br 74.25 74.76

N .25 3.36

The substance is therefore the tetrabromide of pyromucamide.

218 PROCEEDINGS OP THE AMERICAN ACADEMY

Properties of Pyromucamide Tetrabromide. — It is a crystalline
solid without color or odor. Its melting point is about 121°, as
determined in the ordinary way, but it varies with the rapidity of
the heating. By long heating the substance will melt, always
with evident decomposition, even below 100°. It is insoluble in
water, almost insoluble in ether, chloroform, glacial acetic acid, or
alcohol, somewhat more readily soluble in ethyl acetate and ace-
tone. It is decomposed by boiling with water, alcohol, or glacial
acetic acid. When it was dissolved in alcohol and treated with
zinc dust in the cold, the bromine was abstracted and pyromuca-
mide formed. On boiling with water it is decomposed; hydro-
bromic acid is formed, but no definite organic compound could be
isolated. In order to study the products formed by the action of
alkalies, the tetrabromide was added gradually, in small portions,
to cold concentrated alcoholic sodium hydroxide. After standing
in the cold for about an hour, the mixture was allowed to remain
for several days in a warm room, the alcohol being renewed when
necessary. Ammonia was slowly evolved. The alcohol was then
evaporated off, and the solid residue treated with water. Only a
very small portion of insoluble matter was left. This was filtered
off. On acidifying the filtrate, an acid was precipitated which was
purified by converting it into the barium salt, and separating the
latter by fractional crystallization into three portions. The acid
was then liberated from each portion separately. It appeared to
be /3y-dibrompyromucic acid, since each fraction melted at about
192°, the purest at 191°. 5. To remove all doubt, this portion was
dissolved in absolute alcohol, and converted into the ethyl ester
by the action of dry hydrochloric acid. The observed melting
point of the ester, 67°. 5, completed the proof as to the nature of
the acid, since the /3-y-dibrompyromucic acid melts at 191-192°,
and its ethyl ester at 67-68° .* /38-dibronipyromucic acid does not
seem to be formed at all in this decomposition of pyromucamide
tetrabromide. Even microscopic examination failed to prove its
presence, though the crystals are quite characteristic. This is
interesting in consideration of the fact observed by Hill and San-
ger,* that the tetrabromide of pyromucic acid yields, under similar
circumstances, a mixture of the two isomeric dibrompyromucic acids
(/3yand/3S).

* These Proceedings, XXI. 155 el seq.

OF ARTS AND SCIENCES. 219

The Action of Bromine Water on Pyromucamide.

Some remarkable color reactions observed by Professor Hill, when
studying the action of bromine and potassium hydroxide on pyro-
mucamide, led to the suggestion that interesting results might be
obtained in that direction by further work. The author therefore
gave a short time to the study of the nature of these color reactions,
as well as those produced when bromine water is used in place of
pure bromine, and when other basic substances are used in place of
potassium hydroxide.

Pyromucamide treated with bromine water dissolves readily,
producing a solution almost or quite colorless. This was treated
in various ways in order to isolate, if possible, some definite sub-
stance from it, but amorphous dark products were always obtained.
If to the fresh solution there is added almost any strongly basic
inorganic substance, a dark blue (or sometimes purple) color is
soon produced, the rapidity of its production depending apparently
on the strength of the base. The color usually changes to purple
in a short time, and afterwards undergoes other alterations, gener-
ally passing to red, and finally, if the amount of pyromucamide
used is small, fading to pale yellow. When the base employed is
barium hydroxide, a dark blue amorphous precipitate is produced.
An investigation was made as to the quantity of bromine required
to produce the maximum intensity of color from a given amount of
pyromucamide. Measured quantities of dilute solutions of pyro-
mucamide and bromine were mixed, shaken, and allowed to stand
a few moments. Then an excess of sodium hydroxide was added,
and the colors produced were compared. It was found that two
atoms of bromine to each molecule of pyromucamide gave the deep-
est color on subsequent treatment with alkali. Either a deficiency
or an excess of bromine is unfavorable to the color production.
The dark blue compound was too unstable for isolation.

The production of this color may serve as a very delicate test for
pyromucamide. When one milligram of the amide is dissolved in
a drop of dilute bromine water, and the solution made alkaline,
the blue (or purple) color produced is quite distinct.

Chlorine water can be used instead of bromine water, but the
color was not obtained when iodine or nitric acid was emplo3red.
Substituted pyromucamides, so far as investigated, do not give the
color reaction: S-methylpyromucamide, )3S-dibrompyromucamide,
and /3y-dichlorpyromucamide were tried.

220 PROCEEDINGS OF THE AMERICAN ACADEMY

If, instead of sodium hydroxide, an aqueous solution of aniline is
added to the solution of pyromucamide in hromine water, a reddish
precipitate is produced. This substance is not stable. It melts at
about 78°, and appears to undergo decomposition when treated with
alcohol even in the cold.

By substituting a saturated aqueous solution of phenyl hydrazine
for aniline, a brilliant red precipitate was obtained. The most
convenient method for preparing this substance is as follows.
Dissolve a weighed amount of pyromucamide in as small a quantity
of water as convenient ; add to this bromine, a few drops at a time,
shaking the flask and keeping it cool, until for each molecule of
pyromucamide two atoms of bromine have been added. The bro-
mine will be dissolved, and the solution will be almost colorless.
Filter if necessary, and add a large excess of a saturated solution
of phenyl hydrazine in water. Allow the mixture to stand for
some time, filter off the red precipitate formed, wash with water,
then with two or three small portions of alcohol, and lastly with
ether. Dry over sulphuric acid or in a steam-drying oven. The
yield is about 1.6 times the weight of the amide taken. The sub-
stance as thus obtained is bright red in color. It has no definite
melting point, but darkens in color between 150° and 160°. It is dis-
solved, and probably decomposed, by aqueous or alcoholic potassium
hydroxide, with a marked increase in the intensity of the red color.
It is very slightly soluble in chloroform, ether, and carbon disul-
phide, somewhat more readily in alcohol and acetone. Boiling
with alcohol and other solvents decomposes it, but it can be ob-
tained in small scale-like crystals by making a saturated solu-
tion at 50° in alcohol or acetone, and allowing it to cool and
evaporate spontaneously. The crystals are darker in color than
the amorphous material, and are quite brilliant. Qualitative tests
showed the absence of bromine. Analyses of the substance, both
in the crystalline and the amorphous state, were made with identical
results.

The material used in analyses I. and II. was crystallized from
acetone, washed with ether and dried at 100°, while in analyses
III. and IV. an amorphous preparation was used which had been
washed successively with water, alcohol, and ether, and dried over
sulphuric acid.

I. 0.3001 grm. substance gave 0.6684 grm. C02 and 0.1423
grm. H20.

II. 0.1005 grm. substance gave 17.2 c.c. of moist nitrogen at
23°. 5, and 754 mm. pressure.

OP ARTS AND SCIENCES. 221

III. 0.1740 grm. substance gave 0.3879 grm. C02 and 0.0857

grm. H20.

IV. 0.2196 grm. substance gave 37.9 c.c. moist nitrogen at 21°. 5,

and 741 mm. pressure.

Calculated for

Found

CuHuNsO,.

Crysts

illine.

Amorphous.

I.

II.

III. IV,

c

60.83

60.74

60.80

H

5.07

5.27

5.47

N

19.35

19.08

19.1

Tbe formula of tbe substance CnHnNgOa sbows that it contains
the elements of one molecule of phenyl hydrazine, and one of pyro-
mucamide, less two atoms of hydrogen. Lack of time prevented a
more extended study of this body, but the investigation will be
continued at some future time in this Laboratory.

222 PROCEEDINGS OF THE AMERICAN ACADEMY

XV.

CONTRIBUTIONS FROM THE PHYSICAL LABORATORY OF THE
MASSACHUSETTS INSTITUTE OF TECHNOLOGY.

XXXVIII. —ON THE LEAST NUMBER OF VIBRATIONS
NECESSARY TO DETERMINE PITCH.

By Charles R. Cross and Margaret E. Maltby.

Presented May 24, 1892.

The present paper is an extension of one by the same authors
read at the meeting of this Academy held on June 10, 1891, but not
hitherto published. In the investigation described in it a method
was employed which was originally proposed by one of the writers
a number of years since in a paper read at the Philadelphia Meeting
of the American Association for the Advancement of Science, and
published in abstract in the Proceedings for 1884, Vol. XXXIII.
p. 114.

In that paper attention was called to a defect in the method em-
ployed by Savart and Kohlrausch, from which they concluded that
at least two complete vibrations are necessary to characterize pitch.
This defect is a consequence of the character of the vibrations im-
pressed upon the air by the blows produced by the teeth of the
wheel of Savart or the comb of Kohlrausch.

The statement of this difficulty in the paper referred to is as
follows : —

"A cardinal defect in these methods of investigating the point
in question is that the sound produced by a toothed wheel is very
impure; first, because the noise of each separate impulse is mingled
with the note produced by the coalescence of the separate impulses;
and second, because the proper note, determined by the number of
impulses, is itself far from simple in its character. To obtain re-
sults that are fully satisfactory the vibrations utilized should be
pendular (sinusoidal) in their character. I see no reason in the
nature of things why, if a single such simple vibration could be
caused to fall upon the ear, it should not produce the sensation of
a definite pitch. Rather, under the known action of the separate

OP ARTS AND SCIENCES. 223

vibrating parts of the ear, we might suppose that even a small por-
tion of a simple sound-wave, if it produced any recognizable sensa-
tion, would give a sound of a pitch corresponding to the length of
the complete sound-wave, of which a part had impressed the ear."

The method devised in 1884 to remedy the defect consisted of a
telephonic circuit containing two magneto-telephones, connected in
the usual manner for the transmission of sound, and a circuit-mak-
ing wheel. The latter was a wheel of vulcanite, furnished with a
single narrow conducting strip of brass extending over a small arc
of its circumference. Against the edge of the disk pressed a spring
whose end was faced with platinum. If such a wheel is revolved at
a uniform speed, it is clear that once in each revolution the circuit
between the two telephones is closed for a brief period, whose dura-
tion can readily be determined when the speed of the wheel and the
angular extent of the conducting sector are known. If now the
sound of a tuning-fork giving simple harmonic vibrations actuates
the transmitting telephone, the electrical undulation produced will
be a sinusoidal one, and the air-waves produced at the receiver will
be substantially similar in character, and continuous, provided the
contact-making spring rests upon the metal sector of the wheel so
as to complete the circuit. But if the wheel is revolved the electri-
cal current is broken, except during a brief interval of time when
the spring is in contact with the metallic sector; at which period,
however, a current of brief duration is sent through the line and a
correspondingly brief sound is produced at the receiver. Except in
so far as self-induction and like phenomena act to prevent this,
these brief electrical currents are still sinusoidal in character;
and hence should give rise at the receiving telephone to waves or
portions of a wave of sound which are sinusoidal in form, and
should be perceived by the ear as a simple tone. In so far as the
motion of the diaphragm of the receiver deviates from a simple har-
monic one, either from disturbing electrical effects due to self-
induction, or from the acoustic effect of the sudden pull and
L-elaxation which occur when the circuit is made and broken by the
contact-making spring, disturbing sounds will of course be added
to the simple tone, which would otherwise be the only one produced.
But unless the disturbing causes are excessive, the pitch of the
simple tone corresponding to that given by the tuning-fork actu-
ating the transmitter will predominate. And as a matter of fact
these disturbances are slight, as is shown by the fact that there is
no difficulty in transmitting speech through a circuit with a mag-

221 PROCEEDINGS OP THE AMERICAN ACADEMY

neto-transrnitter at one end and a magneto-receiver at the other,
when a rapidly revolving circuit-breaking wheel is interposed to
interrupt the current as many as thirty times per second and
upwards. At high rates of circuit-breaking the high-pitched note,
due to the interruptions, is simply added to the vocal sounds
transmitted.

In practice, however, a slight modification of the apparatus de-
scribed was found to be necessary. As had been surmised when the
apparatus was originally devised, clicks and scratches wrere heard
in the receiving telephone when the current was rapidly made and
broken by the revolving wheel. These often masked the proper
sound of the fork. They seemed to be due to microphonic action
at the contact of the spring and brass segment; and although we
found that this could often be avoided by careful smoothing of the
contact surfaces and proper adjustment of pressure, yet it was
difficult to keep the apparatus in good adjustment. For this
reason, we substituted for the vulcanite wheel a brass wheel having
a single insulating segment of vulcanite. The receiving telephone,
whose resistance was 115 ohms, was placed in derivation with the
brass wheel, so that during the greater part of the time the receiv-
ing telephone was short-circuited and no sensible current passed
through it, as the wheel had very slight resistance. But whenever
the spring rested on the vulcanite segment the circuit through the
wheel was broken; and hence a current passed through the receiv-
ing telephone and produced a sound. This arrangement obviated
the difficulty just referred to, although care had to be taken to keep
the contacts in good condition, as otherwise more or less of a
scratching sound was introduced. In order to reduce the resistance
of the short circuit through the wheel to a minimum, the current
was caused to enter the wheel in the following manner. A disk
made of sheet copper was attached to the axle carrying the brass
wheel. The edge of the copper disk was amalgamated, and its
lower portion dipped into a trough of mercury, thus always secur-
ing a good contact. When the current was made to enter the wheel
in other ways that were tried, as, for example, through a second
spring, it was sometimes found that the resistance of the wheel
circuit was not sufficiently low entirely to prevent the production
of a sound by the derived current that under these circumstances
constantly entered the receiving telephone. With the arrangement
described the apparatus worked very satisfactorily, no trace of
sound being audible in the receiving telephone except when the

OF ARTS AND SCIENCES. 225

spring rested on the vulcanite strip, in which case the pitch of the
fork was perfectly clear. A key was inserted so that the sound
produced at one or more successive contacts could be caused to
enter the ear at will.

In our first experiments we employed as a source of sound a large
tuning-fork vibrating in front of a resonator and sounded by a ham-
mer. But we found that this gave too feeble a sound for our pur-
pose. We therefore made use of a small fork, which was set into
vibration by a blow, and whose stem was lightly pressed against
the disk of the transmitting telephone. A bit of wax placed at
the end of the stem was found to be sufficient to prevent any
chattering.

The particular form of magneto-telephone which was found most
satisfactory as a transmitter, on account of its power, was a bipolar
instrument having a large diaphragm, a special form made by tbe
American Bell Telephone Company. For a receiver we found a
very sensitive form of magneto-telephone made in Sweden best
suited for our purpose.

The tuning-forks employed were of small size, belonging to a
Valentine and Carr tonometer. In all of the experiments cited
the transmitter was placed in a distant room, so that no sound
could possibly reach the ear through the air.

The speed of revolution of the brass wheel was read by a speed-
counter, and from this it was easy to determine the period of time
during which the contact-spring rested on the vulcanite sector.

The mode of observation adopted consisted in driving the wheel
at a rate such that the difference in pitch between the brief sounds
heard in the receiving telephone seemed to be distinct. One of the
experimenters then sounded the forks successively, presenting them
one after another to the telephone, and noting the order in which
they were sounded. The listener at the receiver at the other end
of the line noted the pitch heard, and these estimations were after-
wards compared with the order as noted by the person at the trans-
mitter. The speed was then altered, generally being increased,
and a new set of experiments undertaken. In some cases, owing to
bad transmission or for other causes, the listener felt uncertain
whether the decision noted was correct, and in such cases the result
was marked as doubtful.

In the first series of experiments only two notes were compared,
which were an octave apart; one, C3, of 256 vibrations; the other,
C4, of 512 vibrations.

vol. xxvu. (n. s. xix.) 15

226 PROCEEDINGS OP THE AMERICAN ACADEMY

The following figures will illustrate the general character of the
results. The line marked "T" indicates the order in which the
forks were actually sounded. The line "B," indicates the sound
as noted by the listener at the receiving telephone. The number
of complete vibrations of the lower note transmitted was 0.88; of
the higher, 1.76. The doubtful estimations are followed by an
interrogation mark.

TABLE I.

T. C3 C3 C4 C3 C8 C3 C4 C3 C3 C4 C4 C4
R. C3 C4 C4 C3 C3 C4 C4 C3 C3 C4 C4 C3

TABLE II.

T. C3 C4 C3 C3 C3 C4 C4 C4 C3 C4 C4 C4
R. C3 C4 C4 ? C3 C3 C4 C4 C3 ? C3 C4 C4 C3

In the first of the above series it will be seen that three estima-
tions were wrong, nine right, none doubtful ; that is, 25 per cent
were wrong, 75 per cent right. In the second series one esti-
mate was wrong, two were doubtful, and nine correct; that is,
8.3 per cent were wrong, 16.7 per cent doubtful, and 75 per cent
correct.

The following tables give a synopsis of results reached with the
C3 and C4 forks. Except in a very few cases, twelve successive
sounds were transmitted. The calculated duration of the sound is
in all cases given in terms of the vibration period of both notes.
The percentages are given to the nearest whole number. The first
column contains the serial number of the experiment; the second
(I), the percentage of incorrect estimates; the third (C), the per-
centage of correct estimates; the fourth (D), the percentage of
doubtful estimates ; the fifth (L) and the sixth (H), the dura-
tion of the sound in terms of the period of the lower and higher
notes respectively. The rates are always expressed in complete
vibrations.

OF ARTS AND SCIENCES. 227

TABLE

III.

Forks C3 (256 v.)

, C4 (512

v.).

No.

I.

C.

D.

L.

H.

1

33

50

17

0.88

1.76

2

25

75

0

(C

t<

3

8

92

0

**

«

4

8

75

17

ss

«

5

0

100

0

ss

■<

6

0

100

0

ss

u

7

0

100

0

0 80

1.60

8

8

92

0

<<

"

9

0

100

0

0.73

1.46

10

0

100

0

St

(i

11

17

75

8

0.52

1.04

12

42

58

0

Si

a

13

27

64

9

0 42

0 84

14

50

42

8

a

C<

15 33 67 0

The following results were obtained with intervals other than
the octave.

TABLE IV.

Forks

C3 (256 v.), G3

(384 v

•)•

No.

I.

C. D.

L.

H.

16

25

75 0

0 73

1.10

17

17

83 0

u

it

18

9

83 8

<<

«

19

0

100 0

((

((

20

17

75 8

0*.41

0.62

21

25

67 8
TABLE V.

a

<(

Forks C3 (256 v ), E3

(320 v

■)■

No.

I

C. D.

L.

H

22

33

50 17

0.40

0.50

23

42

58 0

it

St

In the sets of experiments Nos. 22, 23, the contact-spring failed
to give even pressure ; and it was noticed that the sound was very
badly transmitted at certain times, which corresponded with those
at which some of the erroneous estimates were made.

228 PROCEEDINGS OF THE AMERICAN ACADEMY

TABLE VI.

Forks C3 (256 v.), C3 (260 v.).

No.

I.

C. D. L.

H.

24

58

25 17 0.40

0.41

25

25

75 0

t<

It appears from the results given in the preceding tahles that
even with as small a fraction as -j*02q of a vibration of the lower fork
and y^o of a vibration of the higher fork, when these had an interval
of an octave, it was possible to distinguish one note from the other;
and when the duration of the tone was greater, but still much less
than two complete vibrations of the higher note, the distinction
became easy. Nor was the distinction possible merely because of
the possession of a clearly defined pitch by the higher note alone,
whose period was shorter, so that a greater number of vibrations
entered the ear in the time during which the circuit was completed
through the telephone; which, it might be surmised, would enable
one to distinguish it from the lower note even in the absence of any
clearly defined pitch for this latter. On the contrary, the ear al-
ways recognized the existence of a distinct pitch with each note,
even with the shortest duration of tone which was employed in the
experiments; but, as would be expected, the ability to determine
with certainty which of the two notes heard successively was the
higher in pitch diminished as the duration of the sound diminished,
and also as the interval between the two notes became less. The
results given in No. 24, Table VI., are curious, and at the time
they were reached seemed to be due to a misjudgment as to which
of the tones was the higher at the beginning of the experiment.
Series No. 25 was made immediately afterwards ; but the notes of
the forks were carefully listened to separately, in order, if possible,
to fix the pitch of each in the mind. As a result three fourths of
the estimates were correct.

In another series of observations several forks were struck ir-
regularly, and an attempt was made to state which fork of the set
used was heard. The listener knew what were the forks compos-
ing the set.

With forks C3, E3, G3, C4, the results given in Table VII. were
reached. The separate series of observations are separated by hori-
zontal lines. The table gives the name and rate of the forks used
in the first two columns. In column V is given the number of

OP ARTS AND SCIENCES. 229

complete vibrations of each fork in the time during which the sound
lasted in the particular experiment referred to; in column 0, the
number of times each fork was sounded; and in column P, the per-
centage of correct estimations.

TABLE VII.

Note.

Rate.

v.

O.

P.

c3

256

2.4

8

100

E3

320

3.0

13

85

G3

384

3.6

11

73

c4

512

4.8

6

83

c3

256

1.3

9

77

E3

320

1.6

14

64

G3

384

2.0

16

69

c4

512

2.6

7

71

c3

256

1.2

10

80

E3

320

1.5

16

62

G3

384

1.8

15

80

c4

512

2.4

9

77

c3

256

1.0

22

64

E3

320

1.3

21

57

G3

384

1.5

22

84

c4.

512

2.0

11

82

c3

256

1.0

14

62

E3

320

1.3

37

57

G3

384

1.5

18

88

c4

512

2.0

8

87

c3

256

C.9

28

68

E3

320

1.1

36

64

G3

384

1.4

27

63

c4

512

1.8

9

100

c3

256

0.9

25

72

E3

320

1.1

34

65

G3

384

1.4

31

71

c4

512

1.8

14

85

Table VIII. contains the results of similar observations made
upon various series of notes.

230 PROCEEDINGS OP THE AMERICAN ACADEMY

TABLE VIII.

Note. Eate. V. 0. P.

C3 256 1.8 21 62

D3 288 2.0 14 57

E3 320 2.3 22 73

F3— 310 2.4 24 71

G3 384 2.7 22 64

A3— 424 3.0 20 80

c3

256

0.4

30

73

D3

288

05

28

78

E3

320

0.5

18

83

G3

384

0.6

21

76

c3

256

0.4

24

54

D3

288

0.5

18

66

E8

320

0.5

23

52

c3

256

0.4

27

81

D3

288

0.5

31

68

c3

256

0.3

48

85

r»3

288

0.3

58

72

cs

256

0.25

42

81

D3

288

0 28

40

72

With the exception of the last three comparisons, which are in-
serted in this place because they were made in immediate connec-
tion with the preceding ones in the same table, the experiments
whose results are given in Tables VII. and VIII. involve a more
serious difficulty in estimation than do those previously consid-
ered; since, instead of having to decide merely which of two notes
is the higher, it is necessary to determine the musical relation of
the various notes in the set sounded. Nevertheless, even with the
shortest observed duration of the sound, the uniform preponderance
of correct over incorrect or doubtful judgments is altogether too
great to be the result of chance.

Moreover, even when the ability to determine which was the
higher of two notes was lost, with briefer durations of the sound
than those recorded in the tables, there was always a clear difference
in the pitch of the two notes; that is, they did not seem like the
same sound.

It will of course be observed that, with the method used by us,

OF ARTS AND SCIENCES. 231

the element of memory enters, since the pitch of each sound must
he carried in the mind. With a direct comparison of the sound
heard through the telephone line with that given by a tuning-fork
sounded by the observer at the receiving end, it is probable that a
still larger percentage of results would be correct. This remains,
however, to be actually proved by experiment.

It will also be noticed from the tables that in some cases it seems
easier to judge correctly when the two tones make a small interval
with each other than when they make a greater one. For example,
see the comparisons of C3 and D3 in Table VIII. That this is true
when the greater interval is an octave might well be expected from
the well known liability to confuse notes of this interval ; but it is
true of notes of other intervals which are not likely to be mistaken
for each other.

It is our intention to extend these observations to briefer and
longer durations of the sound, and to ascertain what number of
vibrations is necessary to recognize the different musical intervals
when these are entirely unknown beforehand. To obtain louder
souuds it may be possible to use a microphone, although we have
avoided this because of the great liability to disturbance of such a
transmitter when strong vibrations actuate it. It has also occurred
to us that we may use a sinusoidal electrical wave, generated by a
peculiar form of alternating dynamo machine, especially devised for
the production of such a current by Mr. F. A. Laws, of the Rogers
Laboratory. This will give a very loud and at the same time very
pure tone. We also intend to study the comparative accuracy of
estimation when each sound is heard only once, as in the observa-
tions detailed in this paper, with that which is obtained when the
sound is repeated two or more times.

The question may be raised, regarding the method employed by
us, whether the sound given out by the diaphragm was really of as
brief duration as we have assumed it to be. It might be questioned
whether the vibration of the diaphragm was not in fact prolonged;
so that while the duration of the electric current was, for example,
considerably less than the time occupied by two complete vibrations,
yet more than two complete sound-waves were actually produced.

Of course, the instant the diaphragm ceases to be actuated by the
electro-magnet of the receiving telephone, it will begin to assume
its natural rate of free vibration; but how minute a fraction of a
second will elapse before it ceases to move at substantially the rate
impressed upon it might seem doubtful. But under the circurn-

232 PROCEEDINGS OP THE AMERICAN ACADEMY

stances of many of our experiments, in which the duration of the
current was from less than one half of a vibration up to one vibra-
tion, it certainly is not possible that the vibration should continue
without entire change of rate and form for from four to eight times
the duration of the forced vibration, which would have to be the
case in order to have two complete sound-waves produced.

Furthermore, the damping effect of the magnet upon a telephone
diaphragm is such as to prevent more than a very slight amount of
persistence of vibration of any kind whatever. This is shown by
the facts that the natural note of the diaphragm of a magneto-re-
ceiver is never perceived in the ordinary use of the instrument, and
that the quality of the sound heard at the receiver is substantially
the same, although wide variations may be made in the dimensions
of its diaphragm. And if the after-tone of the diaphragm persisted
after each pause sufficiently long to produce a recognizable sound
of definite pitch, say for the period of two complete vibrations,
this would necessarily be noticeable in the actual operation of the
instrument, — an effect which is not observed in practice.

Still further, in none of our experiments was there any note ob-
served which corresponded in pitch to the natural note of the
diaphragm, — a note whose pitch was so high that it could not have
failed to impress itself upon our attention had it been present to
any material extent.

These observations seem to show that with ordinary telephone
currents there is no material vibration of the diaphragm of the re-
ceiver after the forced vibration has ceased. With a stronger
current we might expect a certain continuance of the free vibration.
What undoubtedly occurs is, that as soon as the electrical undula-
tions cease to act on the receiver, its diaphragm begins to move at
a different rate, passing to its free rate of vibration with great
rapidity, and assuming this rate unless sooner brought to rest by
acoustic and magnetic damping. This action would probably pro-
duce a noise of constant pitch, and distinct from the sound of the
transmitting tuning-fork.

But although for these reasons it appears extremely unlikely
that the diaphragm could continue to vibrate with its rate substan-
tially unchanged for more than a very minute fraction of a vibra-
tion, it nevertheless seemed desirable to ascertain by actual and
direct experiment whether this is the case.

For this purpose the following apparatus was devised. A Lissa-
jous comparator, with its vibration maintained electrically, was

OF ARTS AND SCIENCES. 233

employed in the usual manner to study the motion of a very minute
glass head mounted upon the diaphragm of a magneto-receiver,
through the coils of which was carried an alternating current. The
glass bead was illuminated by sunlight or the electric arc. The
rate of the fork was 128 complete vibrations per second. The alter-
nating current could be caused to flow through the telephone coils
for a definite time by the same circuit-making wheel which was
used in the experiments already described. As we desired to use a
far stronger current than that produced by the transmitting tele-
phone, we made use of the alternating current from a transformer
excited by a Thomson-Houston alternating current machine, mak-
ing 128 complete alternations per second. The strength of the
current through the coils was varied by a set of resistances made of
incandescent lamps from a maximum of about 100 milliamperes to
a minimum of about 50 milliamperes, an amount vastly in excess
of any telephone current. When the circuit-making wheel was at
rest and in the proper position the curves of Lissajous were clearly
seen. The motion of the bead was very nearly a simple harmonic
one, so that the curves observed were ellipses, passing into the
limiting oblique straight lines. Difficulty was met with from
variations in the rate of alternation of the current, arising from
very slight variations in the speed of the dynamo machine, so that
it was necessary to utilize such moments as were found to be
available when the steadiness was sufficient. It the circuit-mak-
ing wheel is in motion, it is clear that the appearance of the curve
seen will depend upon the duration of the make, or rather upon the
duration of the motion of the telephone diaphragm. If the har-
monic motion of the diaphragm persists for a period equal to one
complete vibration of the fork of the comparator, — or, more strictly,
for a period somewhat longer than this, and depending upon the
relative phase of the two vibrations when the current begins to
flow through the telephone, — it is evident that the curve should be
a complete ellipse; but if the. harmonic motion of the diaphragm
lasts for a less time, then only a portion of an ellipse can be seen;
and this will necessarily be deformed, as the curve must begin and
end on the same vertical line; which is, of course, the vertical line
given by the illuminated bead, as seen through the microscope of
the comparator when no current is passing through the telephone.

The method has not yet been sufficiently perfected to give accu-
rate quantitative results ; but with the rate of alternation as stated,
viz. 128 per second, and with the strong current used, in some

234 PROCEEDINGS OF THE AMERICAN ACADEMY

cases over 500 times as great as the ordinary current furnished
by a magneto-transmitter, with a calculated duration of current
of from g}^ °f a second to gi^ of a second, in no case was a com-
plete ellipse observed. In many cases the duration as determined
from the curve appeared to be substantially the same as the calcu-
lated amount; and when there was a prolongation of the motion it
was evident from the character of the curve that this was due to
free vibration of the diaphragm.

From these results it would appear that the method used by us is
not open to the objection referred to, and that there is really no
material prolongation of the harmonic motion of the diaphragm of
the telephone after the electric undulations have ceased to actuate
it. Moreover, with the very weak current used in the transmission
of the sounds of the tuning-forks in our experiments, any such pro-
longation, if it existed, would of course be far less than with the
strong current used in testing the point immediately under consid-
eration. The effect of an increased rate of alternation ought to be
studied, but the damping effect of the magnet would be greater at
higher rates.

Some other experiments were made, however, with a current
having 256 complete alternations per second, and of a rigorously
simple harmonic form; but much difficulty was experienced in
securing sufficiently equable driving with such means as were
available at the time of the experiment, so that further work in
this direction had to be postponed until better conditions for
steadiness could be secured.

The improbability of any prolongation of the sound vibrations
within the ear itself has been shown by Herroun and Yeo.*

A few experiments were made by us with a view of gaining some
information regarding the free vibration of the telephone diaphragm
after it was pulled to one side and suddenly released. For this pur-
pose a direct current was substituted for the alternating current
used in the experiments already described. The strength of the
current was substantially the same as before. When the circuit-
making wheel completed the circuit, the diaphragm was suddenly
drawn toward the magnet and released quickly, when the circuit
was broken. With a duration of current of about -giv °f a second
the free vibration seemed to last for about the same period. With
a duration of current of ^is of a second, the free vibration lasted

* Proc. Royal Soc, Vol. L. p 318.

OP ARTS AND SCIENCES. 235

from z\^ of a second to ^\^ of a second. With a duration of cur-
rent of Ti5 of a second, the free vibration often lasted as long as
Ti5 of a second. Under these circumstances the curve frequently
showed clearly the character and rate of the free vibration of the
diaphragm.

It is uncertain whether it will be possible to study the duration
of tbe motion of the diaphragm by employing such currents as are
ordinarily used in telephony, as the effect of these is so slight. In
such a research it may prove advantageous to employ two tele-
phones in circuit, each furnished with a mirror, and giving a
fragment of a Lissajous curve when a beam of light is succes-
sively reflected from the mirrors, the momentary current being
sent through the telephones by the circuit-making wheel; or a
telephone with an objective carried by its diaphragm might be
substituted for the fork of the comparator.

Two other methods have occurred to us of investigating the sub-
ject under consideration, which we hope to be able to make use of.
The first of these is to employ the wave siren of Koenig, using a
disk possessing only a single undulation of the sinusoid, or a frac-
tion of an undulation; or, for repeated sounds, an ordinary disk
with only a definite fractional part of the undulations exposed to
the action of the jet of air. Or perhaps the same result may be ob-
tained by the use of a narrower slit than that ordinarily employed,
so that the air jet shall cover only a portion of the sinusoid.

The second method is to employ a phonograph, on the wax cylin-
der of which are impressed sinusoidal undulations produced by the
sound of a tuning-fork. If only a single such undulation, or por-
tion of an undulation, is allowed to remain, after removing the
others by paring away the wax, the diaphragm will necessarily ex-
ecute only a single harmonic vibration, or fraction of a vibration,
when the cylinder is rotated in the ordinary manner.

Rogers Laboratory of Physics,
May, 1892.

236 PROCEEDINGS OP THE AMERICAN ACADEMY

XVI.

THE TROPICAL EAUNAL ELEMENT OE OUR SOUTH-
ERN NYMPHALLNLE SYSTEMATICALLY TREATED.

By Samuel H. Scudder.

Presented November 9, 1892.

It is not a little remarkable that, with the exception of Hypan-
artia (Vanessini) and Diadema (Argynnini), all those genera of the
subfamily Nymphalinse which are essentially tropical or subtropical,
and are represented on the extreme southern border of the United
States by a very few species each, (species which in many cases
must be looked upon as more or less accidental visitors,) belong to
a few tribes which directly follow one another between the Nym-
phalini and Vanessini. Nevertheless they show a great diversity
of forms, and since in the systematic arrangements heretofore given
they have not been so closely connected as they are here conceded
to be, I have thought it well to give the following succinct treat-
ment of them, originally planned for a Manual of our Butterflies.
The account of the early stages is very largely drawn from Wilhelm
Midler's " Siidamerikanische Nymphalidenraupen," but this has
been supplemented from various sources.

Tribe VICTORINIINI.

Butterfly : Antennae very slender, the club moderately stout,
rather short and rather rapidly incrassated, laterally tricarinate
beneath except at extreme tip. Palpi compact, slender, tapering
greatly, the last joint of considerable length. Wings broad with a
feeble angle at the first inferior subcostal nervule of fore wings,
the hind wings crenate with a distinct lobe at the upper median
nervule; cell of both wings open. Last tarsal joint with two rows
of spines beneath. Egg : Subcorneal, provided with few (9-11)
and rather prominent ribs, which increase slightly in height to-
ward but not reaching the pole. Caterpillar at birth : Head
rounded, covered with simple bristles. Trichomes of body bristle-

OF ARTS AND SCIENCES. 237

like, in five longitudinal series on each side, pointed, and longer,
some much longer, than the segments, those of the upper and lateral
rows arcuate and bent forward at tip, the others straight. Mature
Caterpillar : Head with a pair of long diverging coronal spines of
uniform diameter but more or less enlarged at tip and with a few
scattered papilla-seated hairs. Body with long and slender mostly
pointed spines, when pointed terminating in a needle, their sides
furnished sparsely with sessile needles ; all ranged in three series
on the sides, the lowest infrastigmatal, besides a dorsal set. Feeds
on Acanthaceae. Chrysalis: Rather stout and well rounded; ab-
domen without ridges, the basal segments moderately short, the
third and fourth with several central conical spines, similar to the
pointed mesothoracic and frontal tubercles, those of the abdomen
sometimes obsolete; cremaster long and slender.

SYNOPSIS OF OUR GENERA.

Victorina. Butterfly : Last median branch of fore wings very strongly

bowed at the base. Egg : . Caterpillar at birth : Trichomes relatively short.

Mature Caterpillar : Coronal spines of head scarcely enlarged at tip. Chrysalis:
Third and fourth abdominal segments furnished with pointed spines.

Anartia. Butterfly : Last median branch of fore wings normal. Egg : .

Caterpillar at birth : Trichomes relatively long. Mature Caterpillar : Coronal
spines of head clubbed at tip. Chrysalis : Third and fourth abdominal segments
without raised spines, their place indicated by dark spots.

Victorina Blanchard.

Hutterfly : Antennal club relatively slender, about twice as
broad as the stalk. Second superior subcostal branch of fore wings
long, arising before the end of the cell; second inferior subcostal
branch gently bowed at the base; last median branch strongly
bowed at the base, in contrast to that of the hind wings ; tail of
hind wings longer than broad. Fore tarsi of male not half the
length of the tibia. Egg: See tribe; laid singly. Caterpillar at
birth: Trichomes shorter than in Anartia. Mature Caterpillar :
Coronal spines of head terminating in two or three tubercles
which slightly enlarge its diameter. Chrysalis : Frontal tubercles,
mesonotal tubercles, and those of third and fourth abdominal seg-
ments high, conical, and pointed, the last arranged in a transverse
row on each segment. (Victoria; — name given soon after the ac-
cession of Queen Victoria. )

Victorina Stelenes Linn. (Papilio lavinia Fabr. ; Nympha-
lis steneles God.) Butterfly: Upper surface of wings rich dark

238 PROCEEDINGS OF THE AMERICAN ACADEMY

brown, marked with greenish white in a very broad premedian
band crossing the hind wings and half the fore wings, supplemented
on the fore wings by four very large elongated spots in the apical
half of the wing, the lowermost connected with the band and send-
ing a tongue into the middle of the cell; midway between band and
margin a row of large oval green spots, continued on fore wings as
a premarginal series of unequal, round, often faint, whitish spots.
Under surface pale pearly green, the limits of the bands and spots
of upper surface more or less vaguely mapped in ferruginous. Ex-
panse 100 mm. Mature Caterpillar: Coronal spines of head
8 mm. long, red, broadly crimson at base, whitish in the middle,
and brownish at tip. Body velvety black, the spines reddish gray,
a mediodorsal stripe of stiff pile, less abundant than the unequal
papilla-seated pile on the sides. Feeds on Blechum. Other stages
unknown. — S. Fla. ; New Mexico ; perhaps a mere straggler from
the south.

Anartia Htibner.

Butterfly : Antennal club relatively stout, about three times as
broad as the stalk. Second superior subcostal branch of fore wings
short, arising beyond the end of the cell ; second inferior subcostal
branch retroarcuate at base ; last median branch normal, as in hind
wings; tail of hind wings broader than long. Fore tarsi of male
much more than half as long as the tibia. Egg : See tribe ; laid
singly. Caterpillar at birth: Trichomes longer than in Victorina.
Mature Caterpillar : Coronal spines of head clubbed at tip. Chrys-
alis: All the tubercles, including the frontal and mesonotal, ob-
solescent, those of the abdominal segments obsolete, their place
marked only by pigment, (avaprto?, incongruous ; in allusion to its
great difference in markings from its fellows ?)

AnIrtia j!troph.e Linn. Butterfly ; Upper surface of wings,
except upper outer portion of fore wings, washed centrally with
white, with two broad, crenated black-edged fulvous bars across
cell of fore wings, an interrupted brown median line across both
wings (in the hind wings formed of crescents), and three partial
similar lines across the basal half of hind wings, besides a pair of
slender brown crescentic premarginal bands on both wings, on a
light fulvous base, and moderately large round black spots in the
lower median interspace of both wings and the lower subcostal in-
terspace of fore wings. Under surface whitish lilac, with somewhat
similar markings, the fulvous inclining to ferruginous. Expanse

OF ARTS 4ND SCIENCES. 239

nearly 60 mm. Egg and Caterpillar at birth: Unknown. Mature
Caterpillar : Black, the front of the first thoracic segment, the pro-
legs, and the base of many of the spines more or less ochraceous.
Feeds on Lippia. Chrysalis : Smooth and wholly black, except that
the borders of the antennal cases and the stigmatal fissures are whit-
ish, and the cremaster is somewhat ochraceous at base. — Texas,
S. Florida.

Tribe EPICALINII.

Butterfly: Antennae exceedingly slender, the club slender, nearly
always elongate and then very gradually incrassate, feebly unicari-
nate beneath, the carination concealed when the club is elongate
by the infolding of the under surface. Palpi compact, tapering,
subcompressed and rather elongate, the last joint moderately long.
Wings simple, usually broad, the hind wings well rounded, entire
or feebly crenulate; cell of hind wings open, of fore wings open or
closed by a feeble sinuate vein. Last tarsal joint with two rows
of spines beneath. Egg: Short, subcorneal, provided with few
(10-11) not very prominent ribs which increase very slightly in
height toward without reaching the pole. Caterpillar at birth :
Head simple, subtriangular. Trichomes of body bristle-like, very
short and apically knobbed, arranged in five longitudinal series on
each side, three above the spiracles. Mature Caterpillar : Head
subquadrate, supporting a pair of excessively long, widely di-
verging subequal horns, armed with more or less whorled spine-
lets. Body armed with long, ranged, corneous, sparsely aculiferous
spines, occasionally furnished with one or two spinelets, and always
crowned by an independent needle, some of the spines occasionally
reduced to warts; there are a dorsal series, and two other pairs above
the spiracles, all the developed spines of nearly the same length.
Feeds on Sapindacea?, Euphorbiacece, and Urticacese. Chrysalis :
Smooth, somewhat depressed, especially on abdomen, which tapers
rapidly and has no ridges; a slight mesothoracic carina, sometimes
produced to a point, prominent wing tubercles and short conical
frontal tubercles ; cremaster broad.

SYNOPSIS OF OUR GENERA.

Eunica. Butterfly : Two superior subcostal nervules arising in the fore wings
before the end of the cell, which is closed; costal and median veins much
swollen at the base. Mature Caterpillar: Coronal horns of head with a very few
opposed spinelets. Body subcylindrical.

240 PROCEEDINGS OF THE AMERICAN ACADEMY

Di^ethria. Butterfly: Eyes pilose. First superior subcostal nervule of
fore wings arising at end of cell, which is open ; costal and median veins moder-
ately swollen at base. Mature Caterpillar : Coronal horns of head with a few
spinelets arranged in whorls. Body stoutest in the middle.

Mestra. Butterfly: Second superior subcostal nervule of fore wings arising
at end of cell, which is closed; only the costal nervure swollen at base. Fore
tarsi of male excessively short. Mature Caterpillar : Unknown.

Eunica Hiibner.

Butterfly: Antennal club long and slender, very gradually in-
crassate. Eyes naked. Eirst and second superior subcostal
brandies of fore wings arising before the end of the cell; cell
closed by a feeble vein; both costal and median veins much swollen
at the base. Eore tarsi of male as long as the tibia. Egg and
Caterpillar at birth: Distinctive features undescribed, the eggs
laid singly. Mature Caterpillar : Coronal horns of head curved at
tip, furnished with only a very few opposed spinelets. Body of
nearly equal thickness throughout, the developed spines ending in a
straight thorn. Feeds on Sebastiana (Euphorbiaceae). Chrysalis :
Mesothoracic carina feebly developed. (Eunice, a Nereid.)

Eunica monima Cram. (Nymphalis myrto God. ; Cybdelis
hyperipte Edw. nee Hiibn. ; E. modesta Bates.) Bxttterfly : Up-
per surface of wings soft blackish brown, the apical half of the
fore wings black, the whole with exceedingly faint purplish reflec-
tion; two distant straight oblique rows of rather small more or
less obscure whitish spots cross the apical black field of fore wings,
the inner of three, the outer of two spots. Under surface gray-
brown, the hind wings and apex of fore wings with a faint bluish
tinge, the markings of the fore wings repeated, but the black not
reaching the apex, the hind wings crossed by three wavy dark
brown lines, the outer submarginal, and between it and the median
line a transverse series of very faint, finely brown-edged ochra-
ceous ocelli with minute black pupils, that in the upper subcostal
interspace blue-pupilled. Expanse 45 mm. Early stages : Un-
known. — Texas, Florida.

Di^thria Billberg.

Butterfly : Antennal club rather short, rather rapidly incrassate.
Eyes briefly and sparsely pilose. First superior subcostal nervule
of fore wings arising at the end of the open cell; costal and median
veins moderately swollen at the base. Fore tarsi of male as long as
the tibia. Egg and Caterpillar at birth : Distinctive features un-

OP ARTS AND SCIENCES. 241

described, the eggs laid singly. Mature Caterpillar : Coronal
horns of head straight, with stellate or whorled arrangement of the
few spinelets. Body enlarged in the middle and tapering, espe-
cially behind, many of the developed spines ending in two unequal
thorns directed forward and backward. Feeds on Trema (Urti-
cacea3). Chrysalis: Distinctive features undescribed. (6Yai#po?,
quite fine.)

Di^thria clymena Cram. (Callicore janeira Feld. ; C. clym-
ena var. meridionalis Bates.) Butterfly: Upper surface of wings
rich velvety black marked with bright blue, the fore wings crossed
by a narrow outwardly crenate belt not reaching either margin
from within middle of costal to near end of inner margin, where
the scales are metallic; and by a brief preapical slender transverse
line; the hind wings with a premarginal, rather narrow, equal
band not quite crossing the wing. Under surface of fore wings
crimson on more than the basal half, black beyond, crossed near
tip by two strongly arcuate, inferiorly tapering white stripes, the
inner the broader; hind wings velvety black, the costal margin
marked by carmine, the disk with two large irregular double white
rings partially encircled by two common larger ones, the outer
almost marginal. Expanse 40 mm. Egg: Broad at base, nearly
hemispherical, with 10-11 vertical ribs and very delicate cross lines;
laid singly. Caterpillar at birth : Head simple and with body
green. Mature Caterpillar : Head green, the coronal horns exces-
sively long, straight, brownish green, green posteriorly, having
four or five equidistant whorls of spinelets. Body yellowish green
with yellowish subdorsal stripes and white papillae. Length 22 mm.
Feeds in Brazil on Trema micrantha. Chrysalis : Velvety green
on back, pale green below; a white and brown stripe follows the
alar ridges, continued on the abdomen as an infrastigmatal stripe;
white points occupy the position of the subdorsal spines of the cater-
pillar. — Has been known to occur once in S. Florida.

Mestra Hiibner.

Butterfly : Antennal club long and slender, gradually incrassate.
Eyes naked. Second superior subcostal nervule arising at the end
of the cell, which is closed by a slender vein; costal nervure very
much swollen at the base. Fore tarsi of male excessively short.
Early stages : Unknown. (Derivation obscure.)

Mestra amym6ne Menetr. (Cystineura dorcas Edw.) Butter-
fly : Upper surface of fore wings white, the base and costal and

VOL. XXVII. (n. S. XIX.) 16

242 PROCEEDINGS OF THE AMERICAN ACADEMY

outer margins light brown, the costal margin with a triangular tooth
of brown beyond the cell, the outer margin more broadly bordered
above than below and often tinged next the edge with yellow;
hind wings fulvous yellow outwardly, the extreme margin brown,
pale gray at base with a median and more obscurely a prebasal
transverse white band broadest on the costal margin. Under sur-
face ochraceous yellow with the white markings of the upper
surface repeated, the prebasal band of the hind wings distinct
and brown-edged, the median band more or less broken into un-
equal brown-edged sometimes confluent roundish spots. Expanse
44 mm. — Texas, September.

Tribe GYN^ECIINI.

Butterfly : Heavy bodied. Antennae moderately stout but long,
the club slender, elongate, gradually incrassate. Palpi compact,
moderately slender, tapering, the last joint rather short. Wings
simple, subtriangular, broad, especially the hind pair at its sub-
truncate outer margin, entire, the hind pair sometimes with a small
anal lobe; cell of both wings closed by a slender vein. Last tarsal
joint with two rows of spines beneath. Egg : Conical, with about
11 very prominent vertical ribs nearly reaching the pole. Cat-
erpillar at birth : Trichomes of body shorter than the segments,
straight, delicately clubbed at apex, finely toothed. Mature Cater-
pillar : Head thorny, crowned by a pair of thorny spines longer
than the head and similar to those of the body, which are long,
corneous, surmounted by a whorl of spinelets as important as the
terminal thorn, in ranged series, one mediodorsal as important as
the others. Feeds on Urticaceoe. Chrysalis : Slender and elon-
gate, straight, tuberculate, especially at anterior extremity, bear-
ing a rude resemblance to that of Papilio s. s. or Thais, some of
the tubercles of the laterodorsal series prominent and directed
downward.

Smyrna Hiibner.

Butterfly : Body very robust. Eyes naked. Second superior
subcostal nervule of fore wings arising before the tip of the cell,
the third well before the middle of the wing and extending to the
very apex; lowest median nervule of hind wings produced to a short
lobe. Caterpillar : Only the second stage is known, showing it
to be similar to that of the tropical Gynsecia. (o-fjivpva, myrrh;
allusion wholly obscure.)

OF ARTS AND SCIENCES. 243

Smyrna karwI xskii Htibn. Butterfly : Upper surface of fore
wings dark brownish tawny at base, black at apex, the colors sepa-
rated by a straight oblique pale yellow stripe, broad above, tapering
below, its inner limit just bordering the cell; three large roundish
white spots in a similarly oblique row just before the apex; hind
wings dark brownish tawny, margined broadly above, narrowly be-
low, with black. Under surface of fore wings brown at base, followed
by a transverse broad oblique slightly arcuate pale yellow band,
beyond black, separated from the mottled apex by the repetition
of the spots of upper surface; hind wings light gray brown, the basal
half or more crowded with concentric, more or less oval but irregu-
lar rings of blackish brown, centring, where most regular, in the
costo-subcostal and medio-submedian interspaces, the whole out-
wardly limited by an exceedingly irregular indented line, having its
farthest extension in the costo-subcostal interspace and on the sub-
median nervure; outer portion clouded with dark brown in inverted
lunules, centrally marked with two large and two slightly smaller
and brighter slightly ovate multicolored ocelli. Expanse 90 mm.
Earhj stages : Unknown. — Texas, New Mexico; accidental.

Tribe COEINI.

Butterfly : Very heavy bodied and large, with very short abdo-
men. Antennae naked throughout, stout but long, the club not
much enlarged, subcylindrical, elongate, gradually incrassate, both
club and stalk delicately bicarinate on the inner lower surface.
Palpi very compact but not slender, rapidly tapering and pointed,
appressed, the last joint short and rapidly tapering. Wings large
and broad, the apex of the fore wings broadly produced, the hind
wings with the outer margin rounded subtruncate with or without
tails; cell of both wings open or closed; penultimate superior sub-
costal nervule of fore wings hugging the main stem for half its
length and then suddenly divergent. Last tarsal joint with two
rows of spines beneath. Egg and Caterpillar at birth : Unknown.
Mature Caterpillar : Head with a pair of short prickly coronal
horns. Body armed with ranged thorns having a preapical whorl of
spinules ; besides the dorsal series there is but a single row on either
side above the spiracles, so that the sides of the body are widely
exposed. Feeds on Urticaceoe. Chrysalis : Rather elongate,
compressed, with a dorsal keel and a series of stiff dorsal thorns,
preapicall}T whorled with spinules, on the principal abdominal seg-

244 PROCEEDINGS OP THE AMERICAN ACADEMY

ments; frontal tubercles formed of rather long, cylindrical curved
projections; cremaster broad but pointed.

SYNOPSIS OF OUR GENERA.

Coea. Butterfly : Cell of both wings closed ; hind wings tailed. Early
stages: Unknown.

Histoeis. Butterfly: Cell of both wings open ; hind wings entire. Mature
Caterpillar: Head with enormously clubbed coronal appendages. Chrysalis:
Dorsal spines of abdomen on anterior edge of segments, and 4-5 rayed at apex.

Coea Hubner.

Butterfly : Antennae less than half as long as the fore wings ;
fore wings with the cell closed and the third superior subcostal
nervule arising at or beyond the middle of the wing; hind wings
with cell closed and the upper median nervule prolonged to a slen-
der tail. Early stages : Unknown, (/coe'cu, i.e. one who perceives ;
see the next genus.)

Coea acheronta Fabr. (Pap. cadmus Cram. ; Pap. pherecy-
des Cram.) Upper surface of fore wings tawny fulvous at base,
separated from the black apex and outer margin, sharply above,
vaguely below, by a line which crosses the outer part of the cell
obliquely to the centre of the upper median interspace and then
zigzags toward the lower outer angle ; the black apex has six sub-
quadrate or triangular white spots, four in an oblique series and
two beyond, irregularly placed and unequal ; hind wings rich dark
brown, the basal half with fulvous hairs. Under surface of various
shades of brown, enlivened by areas of blue, lilac, and nacreous, the
basal half slightly the darker and limited outwardly by a strongly
and irregularly crenulate black line, which on the hind wings sends
a long loop outward along the upper side of the submedian nervure ;
other large subocellate black-edged markings occur in the basal
half of the wings, a broad submarginal sprinkling of dark brown
and lavender scales before the tail of the hind wings, and a nearly
straight dark ferruginous cloudy streak across the middle of the
outer half of both wings starting from a subapical white spot on
the costal margin of the fore wings. Expanse 85 mm. — Texas,
New Mexico; accidental visitor.

Historis Hubner.

Butterfly : Antennae half as long as the produced fore wings ; these
with the cell open and the third superior subcostal nervule arising
well before the middle of the wing; hind wings with the cell open

OP ARTS AND SCIENCES. 245

and no tail. Egg and Caterpillar at birth : Unknown. Mature Cat-
erpillar: Coronal spines of head strongly clubbed apically. Spines
of body terminating in only three spinelets; transversely striped
on the sides with three or four stripes to each segment. Chrysalis :
Dorsal ridge terminating on the abdomen at the posterior limit of
the saddle; alar ridge subobsolete; dorsal spines at anterior edge
of abdominal segments ending in a whorl of four or five spinelets.
(torcup, orie who knows; see preceding genus : allusion obscure.)

Historis orion" Fabr. (Aganisthos o. Bd.-LeC. ; Pap. odius
Fabr. ; Pap. danae Cram.) Butterfly : Upper surface of wings
blackish brown, the hind wings more or less fulvous at base, the fore
wings with a very large bright fulvous patch occupying almost the
whole of the basal half of the wing, and extending as a blunt sub-
triangular offshoot into the middle of the distal half nearly to the
margin; a small preapical ovate whitish spot next costal margin.
Under surface rich dark olive-brown, crossed just within the middle
by a broad finely black and blue edged lighter band which broadens
toward each border, and somewhat similar more basal markings,
besides scattered lilac neckings next the middle of the outer border,
marginal and broad on the fore wings, narrow and submarginal on
the hind wings; other fainter clouded lines. Expanse 120 mm.
Mature Caterpillar : Clubbed coronal horns of head beset with
thorns. Body green, with dark transverse stripes, of which the
anterior of each segment is broader and darker than the others,
which are more or less interrupted. Length 75 mm. Feeds on
Cecropia. Chrysalis: Frontal tubercles granulated; joints of
distal half of antennal cases each writh a small conical tubercle.
Body longitudinally striped with darker and lighter colors.
Length 55 mm. — S. Florida; rare and accidental visitor.

Tribe TYMETINI.

Butterfly: Rather slender bodied, with short abdomen. An-
ternnae long and slender, feebly scaled, the club rather slender,
elongate, gradually incrassate; both club and stalk bicarinate be-
neath interiorly. Palpi rather slender and elongate, triquetral,
apically tapering to a blunt point, the last joint rather short and
not very slender. Wings ample, the fore pair broadly produced at
the apex, sometimes falcate, the hind wings subtriangular with a
distinct anal lobe and an elongate blunt tail at the upper median
nervule; cell of both wings open; subcostal and median veins of

246 PROCEEDINGS OP THE AMERICAN ACADEMY

hind wings nowhere approximate. Legs delicate and short, the
under surface of last tarsal joint with two rows of spines, the
others with four. Egg aud Caterpillar at birth: Unknown. Mature
Caterpillar ; Coronal spines of head exceedingly long, briefly and
abundantly aculiferous, slender, tapering. Body armed only with a
dorsal series of erect tapering filaments on a few segments. Feeds
on the Fig family and Anacardiaceoe. Chrysalis : Not very elon-
gate; frontal projections consisting of long slender tapering fila-
ments, similar ones (flexible ?) crowning the basal wing tubercles,
and still others of varying length forming a dorsal series on the
abdomen.

Makpesia Hiibner.

Butterfly : Body small for the ample wings. Fore wings api-
cally produced, often falcate ; second superior subcostal nervule
arising at the end of the cell, the third far toward the tip of the
wing; hind wings with very long tails. Fore tibia and femur of
male of equal length, the tarsus not half so long; fore tibia of
female much shorter than either femur or tarsi. Mature Cater-
pillar: The dorsal filaments are arranged on alternate abdominal
segments beginning with the second, the last on the eighth being
curved backward apically (much like the anal horn of a hawk-moth
caterpillar) and a little longer than the others. Chrysalis : Com-
pact, laterally compressed, with dorsal and anal carinse; head very
broad, bearing outwardly a pair of slender filamentous processes
much like those of the caterpillar; and similar processes appear on
the mesonotal and basal wing tubercles as well as a dorsal series
on the second to the eighth abdominal segments, the first abdom-
inal, the thoracic, and the cephalic filaments longer than the rest;
cremaster bent downwards, the surface of attachment elongate,
parallel to venter. (Marpesus, nom. propr. )

§ M arpesia proper. Butterfly : Costal margin of fore wings very strongly
arched; hind wings emarginate at upper outer angle, but yet with anterior por-
tion longer than posterior part of fore wings and about as long as their own
inner margin apart from the lobes ; tails subspatulcte. Prevailing colors tawny.
Caterpillar feeds on Ficus and Anacardium.

Marpesia peleus Sulz. (Pap. thetys Fabr. ; Pap. petreus Cram. ;
Timetes eleucha Edw.) Butterfly : Upper surface of wings tawny,
crossed by three common, straight, slender black or dark ferru-
ginous stripes, the inner not reaching the margin of either wing,

OF ARTS AND SCIENCES. 247

subequi distant, but the outer two converging on the hind wings
and bent abruptly outward at the subcostal nervure on the fore
wings, the outer double on the hind wings; the cell of the fore
wings is crossed by another feeble stripe between the inner two;
the outer margin is more or less obscured with blackish brown espe-
cially on the hind wings, where the outer stripe terminates in a
pair of more or less obscure transversely oval ocelli ringed with
white. Under surface dead leaf ($ ) or livid (9) brown, much en-
livened by lighter and darker clouds, the stripes of the upper sur-
face indicated more by light than by dark lines, excepting the
most conspicuous middle stripe of the hind wings, which is also
light-edged inwardly; large faintly indicated obsolescent ocelli
follow the outer margin distantly on both wings, most distinct op-
posite those of the upper surface. Expanse 85 mm. Mature Cater-
pillar: Head obscure yellow, with two black vertical streaks on
the face and a black ocellar spot, the coronal horns with short stiff
hairs. Body reddish brown except the ventral surface and the dor-
sal surface from the third abdominal segment backward, which are
yellow ; the sides are marked in front with round black spots, some
with an oblique white line through them; behind, on most of the
abdominal segments, with long, oblique, generally white-edged
black stripes. Length 36 mm. Feeds on Ficus and Anacardium.
Chrysalis : White or yellow, marked with dorsal and suprastig-
matal rows of pretty large black spots the whole length of the
body, besides a large laterodorsal spot on each side of the meso-
thorax, the filaments and cremaster black. Length 20 mm. —
Florida, Texas; accidental.

Marpesia pellenis God. (M. eleuchea p. Htibn. ; Timetes
eleucha Westw.-Hew.) Butterfly : Upper surface of wings tawny,
crossed by three inequidistant slender black or ferruginous stripes,
the middle one of which is abruptly bent outward at the median
nervure of the fore wings, while the outer, which is double on the
hind wings, fades out on the upper part of the fore wings; the
cell of the fore wings is crossed more or less distinctly by three
other similar stripes; outer third of costal margin broadly bor-
dered with black; a submarginal blackish line on both wings, slen-
derer on the hind pair, and a brown gray field next the margin
in the median area of the hind wings enlivened by white-capped
transversely oval black and gray ocelli. Under surface lighter ($ )
or darker (?) light dead-leaf brown with the stripes of the upper
surface more or less obscurely repeated in ferruginous, accompa-

248 PROCEEDINGS OP THE AMERICAN ACADEMY

nied by a series, distant from the margin, of large shadowy ocelli,
at all distinct only next the anal angle of hind wings. Expanse
S 60, ? 75 mm. Caterpillar feeds on Ficus. — Texas, New Mexico,
Florida; occasional.

§ Ttmetes Boisduval. Butterfly : Costal margin of fore wings gently con-
vex; upper outer angle of hind wings in no way emarginate and yet the
anterior portion no longer than the posterior part of the fore wings and
very much shorter than the much produced inner margin, disregarding the
lohe ; tails tapering or rounded apically. Prevailing colors dark brown.
Caterpillar feeds on Maclura and Morus. (tj/ujjt7]j, an appraiser of values;
allusion obscure.)

Marpesia coresia God. (M. zerynthia Hiibn. ; Pap. sylla
Perty.) Butterfly: Upper surface of wings obscure ferruginous
brown at the base, deepening outwardly nearly to the border to
black-brown, in which, next its outer limit, is a slender, straight,
brown stripe, very faint on the fore wings; outer margin broadly
ferruginous brown, the hind wings with a pair of slender sub-
marginal blackish brown stripes, sharply angulated at the tail.
Under surface with the basal half silvery white, sharply delim-
ited, with two parallel slender ferruginous threads across it fol-
lowed by a narrow, outwardly black-edged brownish red stripe,
the edging deeply crenate; outer half chocolate-brown with the
premarginal stripes of the upper surface repeated dully. Ex-
panse 65 mm. Early stages: Unknown. — Texas, New Mexico;
occasional.

Marpesia chiron Fabr. (Megalura c. Blanch. ; Pap. marius
Cram.; Marpesia chironias Htibn.) Butterfly: Upper surface of
wings brown, with four common, straight, equidistant, tapering,
transverse, blackish brown stripes, the outer two curving inward
on the median area of the hind wings, the whole apex of the fore
wings blackish, crossed by two parallel distant series, one of three,
the other of two, minute white spots, the hind wings with a pair
of submarginal black stripes (blended on the fore wings) and two
subocellate transverse spots above anal angle, besides a minute
orange-centred longitudinally oval spot at extreme angle. Basal
half of under surface dull lilac-white, with four subequidistant
transverse ferruginous threads crossing it, beyond the outer of
which the white is changed to very pale yellow ; outer half
very pale reddish brown faintly cross-striped with iridescent lilac,
with a pair of slender premarginal reddish stripes; the white spots
of the apex are cloudily repeated on the fore wings, the ocelli,

OP ARTS AND SCIENCES. 249

somwehat altered, on the hind wings, and a fine Mack premar-
ginal thread runs helow the tail. Expanse 60 mm. Caterpillar :
Undescribed ; feeds on Morus and Madura tinctoria. — Texas,
occasional.

Tribe AGERONIINI.

Bvtterfly : Antennae very long and rather slender, the club slen-
der, very elongate and gradually incrassate, bicarinate on the
inner side and deeply sulcate between the carinae. Palpi as in
the preceding tribe. Wings ample, simple, the hind wings well
rounded with subcrenulate margin; cell of both wings broad and
closed. Legs moderately stout, compactly clad, the last tarsal
joint with two rows of spines. Egg: Short barrel-shaped or
rounded, with few (about 10) low vertical ribs often run together
above. Caterpillar at birth : Trichomes shorter than the seg-
ments, apically knobbed. Mature Caterpillar : Head subquaclrate,
crowned by a pair of very long, equal or apically enlarged, widely
diverging, briefly aculiferous spines. Body armed with tapering,
briefly aculiferous spines of very unequal length ranged in series
(one or two spines mediodorsal) most important in the upper series
and toward the extremities of the body. Feeds on Euphorbiaceae.
Chrysalis : Slender and elongate, laterally keeled over most of
the body, dorsally gently hunched on mesothorax and sometimes
at base of abdomen, the frontal projections of excessive length,
strongly divergent and tapering.

Amphichlora Felder.

Butterfly: Antennae long, the club long and slender, not more
than twice as stout as the stalk, gradually incrassated. Wings
ample, the fore wings with the costal margin faintly emarginate at
the end of the long cell, the costal vein swollen, the first two
superior subcostal nervules arising near together just before tip of
cell, the third not far beyond it, and hugging the main vein for
the first part of its course; vein closing the cell tortuous and
striking the median vein well before its last forking. Fore tarsi
of male with a flat mat of diverging hairs. Egg: Barrel-shaped,
with 10 vertical ribs; laid singly or in columns. Caterpillar at
birth: See tribe; makes a perch along a midrib with frass and
covers itself with its own dung pellets which rest between the
trichomes. Mature Caterpillar: Coronal spines of head three
times as long as the face; inequality of spines of body less marked

250 PROCEEDINGS OF THE AMERICAN ACADEMY

than in others of the tribe. Feeds on Dalechampia. Chrysalis :
Relatively stout, with rather rapidly tapering abdomen and frontal
horns almost half as long as the body. (a/x<pL, ^Aw/jo's, encompassed
with green, i. e. a spring butterfly.)

Amphichlora fornax Hiibn. (Ageronia f. Hiibn.) Butter-
fly: Upper surface of wings marbled in the most intricate fashion
with black, white, brown, and cerulean blue, the black and brown
appearing to form the ground color, the white occurring almost
entirely on the fore wings and there forming a loose broad band
of large spots running from beyond the middle of the costal border
to the lower outer angle, the blue appearing as lunulate, subcon-
tinuous transverse markings, and next the margin, especially on
the hind wings, as the outer ring of large ocelli having usually a
white or blue pupil ; a sinuous black bar crosses the middle of the
cell of the fore wings having a red spot in its lower half. Under
surface of fore wings as far as middle of cell impure white, beyond
black heavily spotted with pure white, the larger spots comprised
in three transverse parallel bands, in each of which, especially the
middle one, the spots are subequal, but the shorter outer baud Jias
one longitudinal bar greatly larger than the others in its series;
the cellular bar is repeated; hind wings uniform dark brownish
yellow, with a marginal series of black-capped white spots, the
outer half or more of the upper three interspaces filled with elon-
gate black and white ocellate spots, and the following three with a
very small black-capped or encircled white spot near centre of its
outer half. Expanse 75 mm. Egg: Short barrel-shaped with
about 10 uniform vertical ribs, in part blended above, laid in
columns of 5-10 in number. Caterpillar at birth : Not distinct-
ively described; covers itself with pellets of its excrement. Mature
Caterpillar : Dorsal spines of hind end and subdorsal thoracic
spines with numerous small equal spinelets, giving them the appear-
ance of cylindrical brushes; subdorsal and suprastigmatal yellow
stripes, the former edged inferiorly with black, the latter sending
oblique shoots downward and backward toward the stigmata; be-
neath red. Feeds in Brazil on Dalechampia triphylla, ficifolia,
and stipulacea. Chrysalis : Either green or blackish brown, with
a broad unequal whitish dorsal stripe, and an infrastigmatal white
band, which continues forward along the edge of the wing-cases
and unites with its opposite behind the frontal tubercles, involving
also most of the ventral portion of the abdomen. — S. W. Texas;
purely accidental

OF ARTS AND SCIENCES. 251

Amphichloba feronia Linn. (Ageronia f. Hiibn.) Butterfly:
Upper surface of wings almost precisely as in A. fornax, with only
a slightly greater preponderance of blue, and with the red spot ex-
tending also to the upper part of the cellular bar. Under surface
of fore wings also the same, but the hind wings sordid white,
sometimes with a faint yellowish tinge, and with the same mark-
ings, but the premarginal markings of the median area are large,
very broadly white-centred, circular black spots, and in the same
interspaces are traces of the proximal edging of the large ocellate
spots of the subcostal area. Expanse 75 mm. Early stages:
Unknown. — S. W. Texas ; purely accidental.

252 PROCEEDINGS OF THE AMERICAN ACADEMY

XVII.

CONTRIBUTIONS FROM THE CHEMICAL LABORATORY OF

HARVARD COLLEGE.

TRIANILIDODINITROBENZOL AND CERTAIN
RELATED COMPOUNDS.

By C. Loring Jackson and H. N. Herman.

Presented November 9, 1892.

In a paper * published last year by one of us and W. B. Bentley,
two forms of anilidotrinitropbenyltartronic ester were described,
one of which was red and melted at 143°, the other yellow with a
melting point of 122°. We have undertaken a more complete study
of this subject because the existence of these two modifications, if
they are really chemical isomeres, is not explained by any of the
present theories of isomerism, unless indeed this should prove to be
a case of an unsymmetrical nitrogen atom according to the hypothe-
sis proposed by Hantzsch and Werner, f The anilidotrinitrophenyl-
tartronic ester can be prepared in quantity only at a great expense
of time and labor. It seemed wise, therefore, to begin our work by
an examination of some related substances for similar modifications,
as, if such were discovered in the case of a more accessible com-
pound, their complete characterization could be worked out with
greater ease. Unfortunately, as the new modifications obtained
during these experiments were not so well marked as those already
found, they could not be used to advantage for this purpose, and
this work has taken so much time that the fuller study of the two
forms of anilidotrinitropbenyltartronic ester could not be entered
upon before the departure of one of us from Cambridge. The work
contained in this paper, therefore, relates principally to the triani-
lidodinitrobenzol, which we have found appears in both red and
yellow crystals, differing most strikingly in color and habit, but
melting apparently at the same temperature, and passing from one

* These Proceedings, Vol. XXVI. p. 67. t Ber. d. ch. G., 1890, p. 11.

OF ARTS AND SCIENCES. 253

form to the other with great ease, so that it is doubtful whether
they should be considered true isorneres. Nevertheless, it has
seemed to us that, in the present state of our knowledge of isorneres,
a description of such closely related modifications as these might
be of advantage to the science, and we therefore publish our results,
which we think the more interesting because the triparatoluidodi-
nitrobenzol shows an exactly similar behavior. On the other hand,
we have not succeeded as yet in obtaining such forms from the
triorthotoluidodinitrobenzol, although it is possible that they may
exist, but that the second modification is less stable than those of
the anilido and paratoluido compounds.

In searching for isomeric forms of the trianilidodinitrobenzol,
which we have done by a great number of varied experiments, we
discovered a compound of this substance with chloroform having
the formula C6H(C6H5NH)3(N02)2CHC13, which crystallized in
blackish red well formed prisms, but lost its chloroform partially
even at ordinary temperatures. A similar addition product was
obtained with the corresponding para- but not with the ortho-
toluido compound; an attempt will be made in this Laboratory to
trace the limits of this reaction.

Numerous attempts to prepare a second modification of trianili-
dotrinitrobenzol or of anilidotrinitrophenylmalonic ester have led
to negative results without exception, as no change in the full
yellow color or the crystalline form of either of these substances
could be observed, but this result seems so strange in view of the
occurrence of two modifications of the trianilidodinitrobenzol on
the one hand, and of the anilidotrinitrophenyltartonic ester on the
other, that a more careful study of these substances will be made
hereafter, and the work extended to other substances, in the hope
of collecting in time enough observations to determine the cause
of the isomerism of the substituted tartronic ester.

Experiments with Trianilidodinitrobenzol.

In searching for isomeric forms of the trianilidodinitrobenzol we
studied more carefully than before the crystallization of it from
various solvents, and found that, when a mixture of benzol and
alcohol was used as the solvent, it appeared in crystals of two sorts,
one the nearly square prisms of an orange color like that of potassic
dichromate already described, the other as yellow as potassic chro-
mate in bladed crystals, or plates looking like flattened monoclinic
prisms terminated by two planes, or less commonly with square

254 PROCEEDINGS OF THE AMERICAN ACADEMY

ends, which, when the cooling took place rapidly, appeared in cir-
cular groups of little needles. These two modifications differed
entirely in crystalline habit and color, and resembled strongly the
yellow and red forms of anilidotrinitrophenyltartronic ester, the
discovery of which had led us to undertake this work; but whereas
the two esters showed a difference of 21° in their melting points
(red 143°, yellow 122°), the yellow and red forms of the trianilido-
dinitrobenzol melted at the same temperature, 179°. To be sure,
the yellow form turned red at about 140°, but there were no signs
of melting, and we do not feel that such a change from yellow to
orange-red is definite enough to have much significance. The yel-
low form was also much less stable than the corresponding form of
the anilidotrinitrophenyltartronic ester, so that we have not ob-
tained it absolutely free from the orange modification. The best
way for preparing it that we found was to crystallize the orange
form from a mixture of benzol and alcohol containing much benzol,
when a portion of the substance usually appeared in the yellow
form. On the other hand, a single crystallization of the yellow
crystals from a mixture of benzol and alcohol containing but little
benzol was sufficient to convert them completely into the orange
prisms. As it was possible that the yellow crystals might be a
compound containing alcohol or benzol of crystallization, instead
of an isomere, we heated to 100° 0.3190 gr. of the best we could
obtain, which had been air dried, but found that the loss was only
0.0004 gr., showing that this is not the explanation of the occur-
rence of this form.

The presence of a small amount of impurity seemed to be favor-
able to the existence of the modification ciystallizing in plates, as,
if a little tribromdinitrobenzol was present, crystals were obtained
of this form although usually a little more orange in color than that
made from pure material, and these would undergo several crys-
tallizations before they were converted into the orange form. A
sample, which we obtained accidentally, was even more stable, and
owed this stability to an oily impurity, the presence of which was
indicated by the low melting point, and which we finally succeeded
in separating, but only after a great number of crystallizations,
when the substance passed into the orange form; the amount of
this impurity, however, was very small, as shown by the following
analyses : —

I. 0.2522 gr. of the substance gave on combustion 0.G004 gr. of
carbonic dioxide and 0.1086 gr. of water.

OF ARTS AND SCIENCES. 255

II. 0.2197 gr. of the substance gave 31.6 c.c. of nitrogen at a
temperature of 25° and a pressure of 755.4 mm.

Calculated for

Found.

C6H(C6H5NU)3(N02)2.

I. II.

Carbon

65.31

64.94

Hydrogen

4.30

4.79

Nitrogen

15.88

15.95

The substance gave no test for bromine with a copper wire, or
even when treated according to the method of Carius. As the
amount of impurity is so small that we thought it could have no
effect, we have used this preparation for the determination of the
molecular weight of the yellow modification, which, with that of the
orange prisms, was made by the method of Eaoult, using benzol as
the solvent, since preliminary experiments had shown that these
compounds were not sufficiently soluble in glacial acetic acid.

Yellow Plates.
Substance 0.2290 gr. Benzol 10.299 gr. Depression 0°. 27.

Orange Prisms.
Substance 0.2561 gr. Benzol 10.468 gr. Depression 0°.29.

From these results the following molecular weights are ob-
tained: —

Molecular Weight.

Yellow Plates 404

Orange Prisms 413

Calculated for C6H(C6H5NH)3(N02)2 441

There can be no doubt, therefore, that the substances are not
polymeric. The benzol solutions obtained in the determinations
were mixed with a little alcohol, and allowed to evaporate sponta-
neously, (the substance is deposited as a varnish from benzol alone,)
when each yielded as the principal product the modification which
had been originally dissolved in it, although in each case this was
mixed with an insignificant amount of the other form.

From the observations given above we should infer that these
two modifications of the trianilidodinitrobenzol are not true chem-
ical isomeres, but physical isomeres, or perhaps rather that the
substance is dimorphous.

We have made a great many experiments to get other isomeric
forms of the trianilidodinitrobenzol, both by varying the method

256 PROCEEDINGS OF THE AMERICAN ACADEMY

of preparation in every way we could devise, and by treating the
orange prisms with reagents, which usually convert one stereo-
isoineric form into another, but have met with no forms except
the two already described.

Compound of Trianilidodinitrobenzol and Chloroform.

If in crystallizing the trianilidodinitrobenzol a mixture of chloro-
form and alcohol was used instead of benzol and alcohol, dark red
well formed short prisms were obtained entirely different from
either of the forms just described. The whole of the substance
could be converted into these prisms, if the solution in chloroform
and a little alcohol was allowed to evaporate at temperatures from
50° to 70°. This substance, however, proved to be, not an isomere,
but a compound with chloroform, since on heating some of the dry
crystals with sodic hydrate and aniline a strong odor of phenyliso-
cyanide was perceived.

Our first attempts to analyze it showed that the chloroform was
given up partially at ordinary temperatures, but that to drive off
the remainder it was necessary to heat to 100°. Accordingly we
proceeded as follows. A quantity of the orange trianilidodinitro-
benzol melting at 179° was dissolved in warm chloroform, and after
the addition of a little alcohol poured into a large watch-glass to
crystallize; when nearly all the chloroform had evaporated, the
crystals were pressed as quickly as possible between filter paper till
free from adhering chloroform, and then transferred at once to a
stoppered glass tube, in which they were weighed.

I. 1.5012 gr. of the compound lost at 100° 0.3226 gr. of chlo-
roform.
II. 1.4455 gr. of the substance lost at 100° 0.3059 gr. of chlo-
roform.

Calculated for Found.

CeH(C6H5NH)3(N02)2CHCl3. I. II.

Chloroform 21.32 21.49 21.16

The residue was trianilidodinitrobenzol melting at 179°.

Properties of the Addition Compound of Trianilidodinitrobenzol
and Chloroform. — This substance crystallizes in short thick prisms
with both terminations well developed, apparently of the mono-
clinic system, which have a very dark brownish red color not unlike
that of well crystallized potassic ferricyanide, and show a blue re-
flex. The chloroform is not securely held, part of it being given

OF ARTS AND SCIENCES. 257

up even at ordinary temperatures with great rapidity, whereas
heating to 100° is necessary to drive out the last traces. On this
account its presence has only a slight effect on the melting point,
lowering it hy a variable amount not exceeding 3° or 4°. Stand-
ing with alcohol if the crystals are small, or grinding them with
it if they are large, also drives out the chloroform, leaving the
usual orange prismatic form, and the same effect is produced hy
one crystallization from alcohol. Its action with other solvents
was not studied.

Triparatoluidinitrobenzol, C6H(C7H7lSrH)3(N02)2. — 10 grams of
tribromdinitrobenzol were heated with 18 grams of paratoluidine
on the steam bath for eighteen or more hours; the reddish black
product was freed from the excess of toluidine by standing with
dilute hydrochloric acid, followed by careful washing with hot
water, and then purified by crystallization from benzol and chloro-
form. The substance thus obtained was not, however, triparato-
luidodinitrobenzol, but its addition compound with chloroform, as
was shown by the isocyanide reaction, and the following analysis
of the crystals dried by pressing between filter paper.

0.9079 gr. of the substance lost at 100° 0.1798 gr. of chlo-
roform.

Calculated for
C6H(C7H7NH)3(N02)2CHC13. Found.

Chloroform 19.83 19.81

Properties of Addition Compound C6H(C7H7NH)3(N02)2CHCl3.
— This substance crystallizes in long plates terminated at each
end by two planes at a rather sharp angle to each other. It has
a dark brownish red color and loses part of its chloroform even
at ordinary temperatures, but does not seem to be decomposed by
alcohol so easily as the corresponding anilido compound.

In order to obtain the triparatoluidodinitrobenzol the preceding
compound was dried at 100° until all the chloroform had passed off,
and then crystallized from alcohol with a little benzol until it
showed the constant melting point 197°, when it was analyzed
with the following results : —

I. 0.1907 gr. of the substance gave on combustion 0.4707 gr.

of carbonic dioxide and 0.1039 gr. of water.
II. 0.2580 gr. of the substance gave on combustion 0.6351 gr. of

carbonic dioxide and 0.1299 gr. of water.
vol. xxvn. (n. s. xix ) 17

258 PROCEEDINGS OP THE AMERICAN ACADEMY

Calculated for

Found.

C0H(C7H7NU)3(N02)2.

I. II.

Carbon

67.09

67.30 67.14

Hydrogen

5.18

6.04 5.59

Properties of Triparatoluidodinitrobenzol. — This substance crys-
tallizes from a mixture of benzol and alcohol in characteristic acute
rhombic plates of a very dark purplish red color somewhat like
that of well crystallized potassic ferricyanide, but redder and more
purple. It melts at 197°, and is nearly insoluble in ethyl or
methyl alcohol ; freely soluble in benzol or chloroform ; sparingly
soluble in acetone or hot glacial acetic acid, almost insoluble in the
latter solvent when cold.

If the dark brownish red plates of triparatoluidodinitrobenzol are
boiled with alcohol, the alcoholic extract deposits on cooling thread-
like felted crystals of a yellow color, which change to red in the
neighborhood of 180°, and melt at 197° like the original rhombic
plates. We have found it impossible, however, to convert the
whole of the plates into the yellow felted needles by this process.
To prove that the yellow crystals did not contain alcohol of crys-
tallization a portion of the preparation was heated to 120° until con-
stant, when it was found that the loss was not more than would be
mechanically retained by such a very spongy substance. The dried
substance was then analyzed with the following result : —

0.2096 gr. of the substance gave 26.9 c. c. of nitrogen at a tern*
perature of 27°. 5 and a pressure of 758.6 mm.

Calculated for C6H(C7H7NH)3(N02)2. Found.

Nitrogen 14.49 14.10

We should add that 0.3991 gr. of the dark red plates air-dried
when heated to 100° for four hours lost only 0.0004 gr., so that
this substance also is free from alcohol or benzol of crystallization.
These observations show that the triparatoluido compound appears
in two forms similar to those discovered with the anilido compound.
Some other solvents beside alcohol convert the red form partially
into the yellow, notably ether and acetone.

Triorthotoluidodinitrobenzol, C6H(C7H7ISriI)3(N"02)2-

This substance was most conveniently prepared by adding 12 gr.
of tribromdinitrobenzol to 35 gr. of boiling orthotoluidine, stir-
ring the mixture, and allowing it to cool as quickly as possible to

OF ARTS AND SCIENCES. 259

avoid the formation of purple dye stuff. The product was treated
with dilute hydrochloric acid twice, allowing the mixture to stand
for some time, and then washed thoroughly with water, after which
it was purified hy crystallization from benzol and alcohol, or chloro-
form and alcohol, until it showed the constant melting point 243°,
when it was analyzed with the following result : —

0.2691 gr. of the substance gave 34 c. c. of nitrogen at a tem-
perature of 23° and a pressure of 763.3 mm.

Calculated for C6H(C7H7NH)3(N02)2. Found.

Nitrogen 14.49 14.31

Properties. — The substance crystallizes in rather stout pointed
needles of a full red color, which melt at 243°, and are somewhat
soluble in hot ethyl or methyl alcohol, less soluble in either cold;
freely soluble in chloroform, acetone, or hot benzol, not very soluble
in cold benzol; slightly soluble in hot ligroine. Sodic hydrate had
no apparent action on it. An attempt to make a chloroform com-
pound from it led to no result, the substance crystallized from chlo-
roform showing no loss when heated to 120°. Nor have we suc-
ceeded in finding a yellow modification, although we have tried the
methods which yielded such modifications with the corresponding
compounds of aniline and paratoluidine ; we think further experi-
ments of this sort necessary, however, before we can be certain that
such a modification does not exist. The high melting point and
the observations just mentioned indicate that this ortho compound
is decidedly different from the corresponding para compound.

260 PROCEEDINGS OF THE AMERICAN ACADEMY

XVIII.

PRELIMINARY COMMUNICATION ON THE HOST OF
NECTONEMA AGILE, Verk.

By Henry B. Ward.

Presented by E. L. Mark, November 9, 1892.

In a paper on Nectonema agile, published last June,* I endeav-
ored to show, from purely morphological evidence, that, although
known only as a free-swimming adult, this worm must he parasitic
in early life. I suggested further some small fish or crustacean
(Paliemonetes) as its probable host. Last October Prof. J. P.
McMurrich t very kindly sent me a nematode with the following
description: "I obtained last summer from a Palaemonetes this
nematode lying curled up in the thoracic cavity. In general form
it suggests Nectonema, but lacks the lateral bands of setae so
characteristic of the free-swimming form; the parasitic habit may
account for that."

The alcoholic specimen, which was in two pieces when received,
measured 75 mm. in length, and 0.5 mm. in diameter, being thus
longer than auy adult female Nectonema hitherto reported, and
surpassing even the avarage male (68 mm.) in length, so that if
this parasitic worm is Nectonema, the difference in size between
the sexes appears less evident than was stated in the paper cited.
Externally this parasite exactly resembles the adult female Nec-
tonema in all respects except in the entire absence of the rows of
hairs which are found on the cuticula of the median lines of the
latter. Cross sections show conclusively that it is a female Necto-
nema in approximately the same stage of development as that rep-
resented in Figure 58 (Plate IV.) of the paper already referred to.
The thin body wall encloses a crowded mass of nearly developed
eggs, which indicate that this specimen is quite as mature as those
captured free swimming. The cuticula is clearly divided into

* Bull. Mus. Comp. Zoiil, Vol. XXIII. No. 3.

t I desire to return my sincere thanks to Prof. McMurrich for his kindness
in sending me this specimen.

OF ARTS AND SCIENCES. 261

two layers, a superficial broken stratum, of a brownish, hue, and
variable in thickness, which is separated by a sharp line from the
underlying homogeneous bluish layer. The latter is uniform in
thickness and regular in outline. These two layers are slightly
separated at the median lines, and between them may be seen
shreds of cuticular substance, which, to judge from tangential sec-
tions, lie in rows, and are apparently attached to the deeper layer;
they are probably the hairs of the adult. From these appearances
I feel justified in concluding that the outer layer is the last larval
cuticula, which is ready to be cast when the nematode leaves its
host, and the deeper layer is the permanent cuticula of the adult,
which already bears the characteristic hairs. Since this specimen
was practically as far developed as the youngest free form de-
scribed in the previous paper, it was probably nearly ready to
desert its host, and therefore furnishes no new evidence as to the
structure of the female.

The discovery of this individual seems to establish bejrond ques-
tion the parasitic nature of the young Nectonema, and indicates
Pala?monetes as its host. On the analogy of Gordius there is some
reason for supposing that Nectonema may have facultative hosts,
and it may even be that Palremonetes is only an occasional host;
yet that it is normally one can scarcely be doubted in view of the
maturity and perfect development of this specimen. Further, it is
more probable that the development is completed in a single host
than that a change of hosts occurs, and, in spite of the scarcity of
the parasite, one may confidently expect, now that the attention
of investigators has been directed to this host, that all stages of
the development will be obtained.

The results obtained from the study of a single specimen are
necessarily incomplete, and are presented in order to call attention
to the host, in the hope that more material may be obtained, and
also to establish the position taken in my previous paper as to the
parasitic nature of the immature Nectonema. I expect to search
next summer for additional material on the development, and shall
be deeply indebted for any further information as to the occurrence
of this nematode or its host.

Morphological Laboratory,

• University of Michigan.

262 PROCEEDINGS OF THE AMERICAN ACADEMY

Investigations on Light and Heat, made and published wholly or in part with
Appropriation from the Eumford Fond.

XIX.

ON THE THERMAL CONDUCTIVITY OF CAST IRON
AND OF CAST NICKEL.

By Edwin H. Hall.

Presented June 15, 1892.

In" the year 1890, having occasion to construct a thermopile of
nickel and cast-iron, for experiments upon cylinder condensation
in steam-engines, I wished to know approximately the ratio of the
thermal conductivities of these two metals. To my surprise, I
could find nothing in the books examined concerning the thermal
conductivity of nickel. As to the same property in iron there
was considerable information in print, but different experimenters
had found very different values. I therefore determined to seek
the information which I needed by experiment, following the well
known method of Forbes and of Tait, — a study of the permanent
gradient of temperature along a bar heated at one end, in a room
of constant temperature, and of independent observations on the
rate of heat emission from a bar of the same material in the same
room. Forbes and Tait both used a shorter bar for the emission
experiments than for the steady flow. I used the same bar for both
parts of the work. My results, though claiming no great accuracy,
are of some interest to the scientific world, as giving an approximate
value for the thermal conductivity of nickel and of cast-iron.

I had two bars of cast-iron made, each, when finished and thinly
nickel-plated to prevent rusting, about 92 cm. long and 2.52 or
2.53 cm. in width and thickness. One was of ordinary Southern
cast-iron, brittle in quality, specific gravity 7.06; the other was
of so called gun-iron, specific gravity 7.18, which is very much
tougher than ordinary cast-iron. A number of castings were made
for the gun-iron bar before one was obtained that was reasonably
free from blow-holes. No such difficulty was experienced with the
other iron.

OF ARTS AND SCIENCES. 263

To procure a nickel bar as large as the iron ones gave no small
trouble. It was not to be found in the market, but some 23 lb.
of commercial nickel, in various shapes, put into a new melting-
pot by an obliging brass-founder, yielded, after one or two failures,
a casting from which a bar 91.5 cm. long and about 2.55 cm. in
width and thickness was worked out. The high melting point of
nickel makes it a difficult metal to cast in the form of a long bar.
A baked sand mould was finally used, and one end of it was ele-
vated considerably above the other, in order that the whole might
become filled before the metal cooled. Even with this device the
success attained was not perfect, and the finished nickel bar was
marred by many flaws. A little experience, however, shows that
a blow-hole may be of considerable size without deserving to be
counted among the more serious causes of error in the determina-
tion of thermal conductivity. Borings or cuttings from this nickel
bar were analyzed by a chemist, and were found to contain several
per cent of iron, and small quantities of other impurities, of which
silicon was one. All of the nickel put into the melting-pot was
represented when purchased to be fairly pure, but it was discovered
too late that two pounds of it was of very poor quality, that is,
contained much iron.

In each of the three bars holes about 0.55 cm. wide and about
2.3 cm. deep were bored to receive the thermometer bulbs. The
length of each bar was divided into nine nearly equal parts, and
one hole was bored at the middle of each part, so that the holes
were a little more than 10 cm. distant from one another. Each
hole was partly filled with mercury.

The thermometers used with the bars had bulbs about 0.45 cm.
wide and about 2.0 cm. long. They were graduated- for the pur-
poses of this investigation on the basis of bulb-immersion only.
They were not high grade instruments, and some of them were
probably in error nearly 0°.5 at various points between 0° and 100°.
At 100° they read from 0°.l to 0.°3 or 0.°4 low. Above 100° the
errors were more serious, — thermometer no. 8, which was some-
times used with a reading of 150° or higher, having an error of
about 2° at that temperature, according to the comparison afterward
made with a good thermometer lent me by Professor Holman of
the Massachusetts Institute of Technology.

The conduction experiments were made in May and June, 1890,
in the north side of the middle basement of the Jefferson Physical
Laboratory. The bars were supported near their ends on thin

264 PROCEEDINGS OP THE AMERICAN ACADEMY

wooden pillars, about 20 cm. above the top of a long wooden table.
For the steady flow experiments two bars were placed in line with
their ends nearly touching, and both were heated at once by the
same Bunsen flame, which was protected from drafts of air by a tin
casing about 38 cm. tall and 13 cm. square, pierced on two sides to
admit the ends of the bars. The general temperature of the room
was observed by means of six ordinary Centigrade thermometers,
of which one was placed on the table near the heated bar, one about
1.25 cm. above the middle of the bar aud about 30 cm. from the
ceiling of the room, one near the north wall about 2.5 m. distant,
another about equally distant upon a south wall, another some 10 m.
away upon the western wall, and another about the same distance
toward the east. During the experiments on steady flow and on
rate of cooling, the thermometer lying on the table usually read
about 0°.5, and the one hanging above the bar about 2°, higher
than the mean of the six. The mean reading of these six ther-
mometers differed from the mean reading of the eight thermometers
used on the bars less than 0°.l, when all were placed together in
water near 20°. The mean reading of the six room, thermometers
during the actual experiments upon the bars usually varied only a
few tenths of a degree in an hour.

Not wishing to devote a great deal of time to the work in hand,
I was content with a rather rough approximation to a state of
steady flow of heat. The method followed was to take several
rapid observations of all the bar thermometers at five-minute inter-
vals, after they had become reasonably constant. Upon the basis
of such observations calculation was easily made of the rate at
which heat was accumulating in the bar at any given instant. In
some cases this accumulation made a difference of several per cent
in the amount of heat entering into the calculation of the con-
ductivity. As an example of the method of observation, the fol-
lowing series made with the nickel bar will serve, the columns
headed 1, 2, 3, etc., being readings of the thermometers no. 1,
no. 2, no. 3, etc. : —

Time

1.

2.

3.

4.

5.

e.

7.

8.

O

0

0

o

o

o

o

o

12:48

27.4

29.0

32.2

37.7

47.8

63.9

93.5

144.6

12:53

27.5

29.0

32.4

37.9

47.9

63.9

93.2

144.0

12:58

27.6

29.2

32.4

37.9

47 9

63.8

93.1

143.7

1:03

27.7

29.3

32.4

37.9

47.8

63.7

92.7

143.0

OF ARTS AND SCIENCES. 265

From these observations the following estimate may be made : —

Time 1. 2. 3- 4. 5. 6. 7. 8.

O

o

0

o

0

o

0

0

12 : 50^

27.45

29.00

32.30

37.80

47.85

63.90

93.35

144.30

1 : 00£

27.65
27.55

29.25

32.40

37.90

47.85

63.75

92.90

143.35

Means

29.13

32.35

37.85

47.85

63.83

93.13

143.83

Rise in 10

minutes

.20

.25

.10

.10

.00

—.15

—.45

—.95

This was an unusually bad case.

Each bar was tested twice in a condition of approximate steady
flow, that end which was heated in one test being the cool end in
the other test. This trial of both ends in turn was probably sug-
gested by the fact that the ends of the nickel bar were somewhat
different in appearance, owing to that too rapid cooling of the
molten metal which has already been mentioned.

For determining the rate of emission of heat each bar was twice
heated and cooled as a whole. As only eight thermometers were
available for this purpose, the middle hole was left unoccupied in
all the rate-of-cooling experiments. The order of experiments was
as follows : —

Cast Gun-Iron. Southern Cast-Iron Nickel.

May 30, rate of cooling. May 31, rate of cooling. June 10, rate of cooling.

June 2, steady flow. June 2, steady flow. " 11, steady flow.

" 7, rate of cooling. " 4, rate of cooling. " 11, " "

" 11, steady flow. " 11, steady flow. " 12, rate of cooling.

The bars were generally, if not in all cases, rubbed somewhat
to brighten their surfaces just before being used. In experiments
on the rate of cooling the whole length of the bar was first heated
to about 115 or 120°, and as it cooled observations of all the ther-
mometers upon it were made at regular intervals, — two-minute
intervals at first and longer ones afterward, — until the bar was
perhaps not more than 15° (in the earlier cases about 20° and in
the later about 10°) above the general temperature of the room.
The accordance of the two sets of cooling observations made with
each bar was, on the whole, very satisfactory. From each set a
curve was plotted. The following values taken from these curves
will show how close the agreement was : —

266

PROCEEDINGS OF THE AMERICAN ACADEMY

Cast Gun-Iron.

Temp aboye that of Room.

Cooling per Second,

o

o

May 30

30

.0098+

<<

50

.0178+

a

80

.0300

June 7

30

.0102—

a'

50

.0178—

«

80

.0300

Southern Cast-iron.

May 31

30

.0102—

u

50

.0178+

(i

80

.0303—

June 4

30

.0100

«(

50

.0182—

«i

80

.0303+

Nickel.

June 10

30

.0098—

«

50

.0178—

<i

80

.0306—

June 12

30

.0100

ii

50

.0178+

<i

80

.0311—

In order that the air currents in the neighborhood of the bar dur-
ing the cooling experiments might be, as nearly as practicable, like
those prevailing during the steady flow observations, the Bunsen
lamp within the tin protecting case already described was kept
burning near one end of the cooling bar, the flame being of about
the same height in all cases. A screen was placed between the
box and the end of the bar to prevent direct radiation.

No attempt was made to represent by equations the temperature
of the different parts of the bars during the condition of steady
flow. The observations for every case were merely plotted care-
fully, with distances along the bars for abscissae, and with tem-
peratures, minus temperature of the room, for ordinates. Through
the tops of the ordinates a smooth curve was drawn. The gradient
of temperature at any point of the bar was found by measurement
of the inclination of the curve at that point. The mean tempera-
ture of each division of the bar whose surface emission had to be
considered was easily estimated from the mean height of the curve
for that division. The amount of heat emitted from each such
division was then estimated by reference to the curves, already
mentioned, showing rate of cooling as a function of temperature of
metal minus temperature of room. Wherever the specific heat of

OP ARTS AND SCIENCES.

267

iron or of nickel appeared in the calculations, Naccari (Atti della
R. Accademia delle Scienze dl Torino, Vol. XXIII., 1887) was
followed as an authority. He gives these values : —

Sp.

ht. of Iron.

Sp

ht. of Nickel

At 15° C.

0.1091

0.1057

At 50°

0.1113

0.1090

At 100°

0.1151

0.1137

At 150°

0.1196

0.1185

As any curve drawn, even when it runs smoothly and accurately
through the points given by observation, may not represent the
exact condition of things at intermediate points, and as there
is liability to considerable error in determining the gradient of a
line the curvature of which is everywhere changing, the conduc-
tivity was calculated for two points upon each curve of steady
flow, both points lying between the two thermometers nearest the
heated end of the bar. The difference between the two values thus
found from any one curve is not to be explained by variation of
conductivity with temperature. It is due, in the main, to errors
of experiment or calculation. As there are two calculated values
of conductivity from each curve of steady flow, and two such curves
for each bar, there are four calculations of conductivity for each
bar, but no two of these four are entirely independent, for the two
sets of observations on the rate of cooling of each bar were com-
bined for use with each curve of steady flow in that bar. The
results are here presented : —

Southern Cast-Iron.

Conductivity (c. g s.).

Temperature.

End no. 1 heated,
June 2, 1890

•1102 } .1158
.1214 )

at
«

119° C.
106

j 112.5

End no. 2 heated,

•0987 I .0981
.0975 J

a

123

} 116.5

June 11, 1890

«

110

. . . .107

Cast Gun-Iron.

114

Conductivity (c. g. s.).

Temperature.

End no. 1 heated,
June 2, 1890

•1049[.1045
.1042 )

at

116° C.
105

1 110.5

End no. 2 heated,
June 11, 1890

til \ 1036
.1062 )

(C

M

121
109

J 115.0

113

268

PROCEEDINGS OF THE AMERICAN ACADEMY

End no. 1 heated,
June 11, 1890

End no. 2 heated,
June 11, 1890

Mean

Impure Cast Nickel.

Conductivity (c. g. 8.)

.108 / 1Q65 at

.105 S
.1030 > 1062
.1095 )

. . . .106

Temperature

127° C. )

115 )
128 I

116 S

116

117

116

The avowedly rough and hasty character of the experiments
being considered, the agreement of the results obtained in the case
of gun-iron and in the case of nickel is entirely satisfactory. In
the case of the other bar, the results do not agree among themselves
so well as one could wish, although, in view of the acknowledged
difficulty which attends experiments upon thermal conductivity,
they should not be considered surprisingly discordant. I can offer
no explanation of the fact that both the largest and the smallest
calculated values of the conductivity were obtained from this bar.
The mean value, it will be observed, is not very far from the mean
obtained with the gun-iron bar. The mean value for each of the
iron bars is, I believe, smaller than any other investigator has
recorded for iron, though not smaller than has been found for
Bessemer steel.

The following values are taken from Landolt and Bornstein's
Physikalisch-Chemische Tabellen : —

Temperature.

Conductivity.

Observer.

Iron 100°

C.

.1417

Angstrom.

0

.1988

tt

100

.1627

Lorenz.

0

.1665

a

Wrought-Iron 100

.1567

Forhes.

" " 0

.2070

(C

Bessemer Steel 15

.0964

Kirchhoff and Hansemann

According to Kirchhoff and Hansemann ( Wied. Annalen, Vol.
IX. p. 5), the conductivity of iron (in c. g. s. units) is expressed
by the formula .1694 — .00034 (t — 15).

This gives for 15° C. the value .1694,
and for 100° C. the value .1405.

The iron used by Lorenz had the density 7.828 {Wied. Annalen,
Vol. XIII. p. 438), and was therefore not cast-iron. That used by

OP ARTS AND SCIENCES. 269

Kirchlioff and Hansemann (Wied. Annalen, Vol. IX. p. 6) con-
tained only 0.129 per cent of carbon, and was therefore not cast-
iron. I have as yet found no description of the iron used by Ang-
strom, but it is probable that he too used a tolerably pure specimen.
Reviewing the course of my experiments, I find no reason for sup-
posing my values to be, as a whole, much too low. The very great
interval of temperature, about 50°, between thermometers 8 and 7,
next the heated end of the bars, was no doubt too great for the
greatest precision of results, but a number of calculations of the
conductivity for points between thermometers 7 and 6 give a mean
very near those found for points between 8 and 7. The natural
conclusion is, that cast-iron has a much smaller conductivity than
wrought-iron.

But whatever may be the value of my results as to iron alone,
there can be little doubt that the main object for which the experi-
ments were made, namely, to determine approximately the relative
conductivity of cast iron and cast nickel, has been attained. The
thermal conductivity of the nickel here used is very nearly the same
as that of the cast-iron bars with which it was compared.

In spite of the very considerable amount of laborious study that
has been devoted to the thermal conductivity of iron, authorities
differ widely in their conclusions, especially upon this particular,
the change of conductivity with change of temperature, as the
numbers above given show. This difference comes in part from
different opinions as to the change of specific heat of iron with
change of temperature. The work of a number of investigators
within the past ten years has added greatly to our knowledge upon
this latter subject, and possibly recalculations of thermal conductiv-
ity from old observations might now be made with advantage.

I hope soon to make trial of a method for estimating thermal
conductivity somewhat different from any heretofore used.

January 7, 1893.
I have recently, with the help of students, made additional ob-
servations upon steady flow and the rate of cooling in the Southern
cast-iron bar, placed now in the main lecture-room of the Physical
Laboratory. The new observations on rate of cooling extended
about 46° only, — from +110° to +64°; but for this range they
indicated a rate about 10% greater than was found in the base-
ment in 1890. A rough calculation from this new study of the
bar indicates for end no. 1 a conductivity practically the same as

270 PROCEEDINGS OF THE AMERICAN ACADEMY

that found for this end before; but for end no. 2, a conductivity
about 6°f0 greater than previous observations showed.

Chemical analysis of borings from the nickel bar showed the
following composition : —

Nickel 85.44%

Iron 7.56

Silicon 0.42

with small quantities of antimony, arsenic, copper, manganese,
phosphorus, sulphur, and tin.

Analysis of borings from the gun-iron bar showed : —

Carbon (total) 3.64%

Phosphorus 0.59

Silicon 1.33

OF ARTS AND SCIENCES. 271

XX.

CONTRIBUTIONS FROM THE PHYSICAL LABORATORY OF THE
MASSACHUSETTS INSTITUTE OF TECHNOLOGY.

XXXTX. — ON SOME EXPERIMENTS WITH THE PHO-
NOGRAPH, RELATING TO THE VOWEL THEORY
OF HELMHOLTZ.

By Charles R. Cross and George V. Wendell.

Presented May 24, 1892.

The value of the phonograph as an aid in the study of the
theory of vowel tones was recognized almost immediately upon
the invention of that instrument, and it was employed for this
purpose as early as 1878 hy Messrs. Jenkin and Ewing,* and
also hy Dr. C. J. Blake in connection with one of the present
writers. The experiments of the last mentioned observers were
designed to aid in the solution of the question whether it is a fact,
as assumed hy Helmholtz, that each vowel possesses a distinctive
character due to the presence of a particular tone or tones, which
are the resonance notes of the mouth cavity when shaped for the
utterance of the corresponding vowel. The method employed, and
the results obtained were described in a letter to Nature (Vol.
XVIII. p. 93), so that a brief reference to them will suffice.

The plan followed was to speak a vowel into the mouthpiece of
the phonograph when the cylinder was revolved at a certain rate,
and then to reproduce the tone with a varying rate of revolution,
both faster and slower than that used when the record was im-
pressed upon the cylinder. Any particular resonance note, if pres-
ent, would then have its pitch raised or lowered, and presumably
the vowel sound would be correspondingly altered.

This was found to be the case, the vowel apparently changing
with change of speed of the cylinder. For example, the vowel 6

* See Nature, Vol. XVII. p. 384 ; Trans. Roy. Soc. Edinburgh, Vol. XXVIII.
p. 745.

272 PROCEEDINGS OF THE AMERICAN ACADEMY

changed to e on increasing the speed to a rate considerably above
that at which the former vowel was impressed upon the recording
cylinder, and fell to a when the speed of the cylinder was carried
considerably below that at which the record was made.* Various
other results of the same character were secured.

The accuracy of these results was questioned, but they were shortly
afterwards confirmed by A. G. Bell and F. Blake, f and others. The
only form of phonograph in existence at that time, however, remark-
able as it then seemed to be, was extremely crude and imperfect,
the tin-foil employed as a medium for receiving the record not be-
ing well fitted to receive and retain the delicate impressions of the
sounds of the human voice. Upon the commercial introduction of
the modern phonograph of Edison, in which a cylinder of wax re-
places the tin-foil, and which leaves little to be desired so far as
clearness of articulation is concerned, it appeared to be desirable to
repeat the early investigations just referred to, with the improved
instrument. After our work was well advanced, our attention was
called to investigations in the same direction by Hermann. $ But
his very valuable researches on vowel tones, and their study by the
aid of the phonograph, have mostly employed methods other than
the one under consideration, and only some general results by this
particular method seem to have been published by him. These
are in accordance with the observations described in the letter to
Nature already mentioned.

The method followed in the present series of experiments is
identical with that used in the earlier studies referred to. As the
cylinder of the modern phonograph is rotated by an electro-motor
furnished with a good speed-governor, it was easy to vary the speed
within moderately wide limits, and to keep it at a tolerably definite
and known rate, which was done in most of our experiments. In
some of these, however, only general results were sought for, and
no attempt was made to measure the speed.

We proceed to give a detailed description of a few of our more
general preliminary experiments, which is followed by a statement
in tabular form of the later and more precise observations. In the

* In tins paper the sounds of the different vowels are denoted by the con-
ventional signs employed in the Century Dictionary. Certain other signs used
are explained later.

t See American Journal of Otology, Vol. I. p. 163.

| Cent. f. Physiologie, 1890, Vol. IV. p. 242 ; Pfliiger's Archiv, 1890, Vol.
LXXIV. p. 42.

OP ARTS AND SCIENCES. 273

former, we have noted only those sounds which seemed most promi-
nent in the different series.

(1) The vowel 6 was spoken into the speaking-tube of the phono-
graph when the cylinder was rotated at the lowest speed at which
it was possible to drive it with the governor used, — about one
half-revolution per second. The vowel was then reproduced with a
gradually increasing speed of the cylinder up to the highest possi-
ble speed, — about three and one half revolutions per second. The
experiment was repeated several times, and with different observ-
vers. The sounds heard as represented were

6" o ou u a.

(2) The vowel o was spoken into the mouthpiece at a speed of
about one revolution per second. On reproducing it at lower rates
down to about one half-revolution per second, the vowel sound was
still heard as o, but becoming more and more guttural, until at the
lowest speed it sounded like a deep gurgle.

(3) The vowel o spoken with a moderately low speed of the
cylinder, and reproduced with gradually increased speeds from
the lowest possible to the highest, gave the following sounds : —

6 o o ou a a.

(4) The vowel o was spoken into the instrument at the highest
attainable speed, and repeated a number of times, the speed of the
cylinder meanwhile being lowered gradually, so that the vowel in
question was impressed upon the cylinder at a variety of speeds,
from the highest to the lowest. It was then reproduced with grad-
ually increasing speed of the cylinder, beginning with the lowest
possible. This procedure was well adapted to give a large num-
ber of vowel sounds in succession. The reproduced vowels noted
were

6 o o on a a i.

(5) The vowel o spoken at the lowest possible rate was repro-
duced at gradually increasing speeds. The sounds heard were

5 a a e i.

(6) The vowel o spoken at a rate of about one revolution per
second was reproduced at a lower speed as o and at the lowest
attainable speed as a very deep guttural 6.

(7) The vowel e spoken with a cylinder speed of about one revo-
vol. xxvn. (n. s. xix.) 18

274

PROCEEDINGS OF THE AMERICAN ACADEMY

lution per second, and reproduced at speeds varying from the lowest
to the highest attainable, gave the following sounds : —

il e e i.

The last mentioned sound was given out only at the extreme upper
limit of speed.

(8) The vowel e spoken with a speed of about two revolutions
per second was reproduced at a lower speed as u, but at all attain-
able higher speeds still retained its vowel character as e.

The following tables contain the results of later experiments in
which the speed of revolution was measured. Table I. contains
results reached when a single vowel was sounded and reproduced at
various speeds. The first column contains the serial number of the
experiment; the second, the name of the vowel; the third, the rate
of revolution of the cylinder of the phonograph when the vowel was
spoken into the mouthpiece and its record impressed upon the
wax; and the fourth, the vowel sounds observed when the spoken
sound was reproduced at various speeds, Rv The speed is denoted
in revolutions per second.

TABLE I.

No.

Vowel
Spoken.

R

Vowels reproduced.

1

2
3
4

5
6

7
8

0
0

6
a
a
a
a
i

1
1
o

1

3

2
i

1

[Ri \ 1 2 3

( Vowel reproduced . 6 6 ou out (almost aj).

( Kj £ 1 2 3

j Vowel reproduced . 6 o ou out (less sharp

than in 1).

( /?! 1 2 3 2,\

| Vowel reproduced .6 o q ou

t#i \ 1 3

( Vowel reproduced . 6 d a

$Rl 3 2 1 \

| Vowel reproduced . d 6 5 6

</?i \ 1 2 3

( Vowel reproduced .6' o d a

\Rx \ 1 2 2\ 3

( Vowel reproduced . a a a e i

j/?t h 1 2

( Vowel reproduced . e i

OF ARTS AND SCIENCES.

275

TABLE II.

No.

Vowel
Spoken.

9 So
10
11
12
13
14

15 odd.

16 bod
17

e o e

e o e

o e e

18
19
20

a o o

o e a i o

o a i o e

o o a e i

Vowels reproduced.

\l?i 1 2

( Vowel reproduced . So 5 ou

I i?! 1 2

\ Vowel reproduced . 6 o ou 6

( /?, 1 2 3

"j Vowel reproduced . e e 5 e e ou e e a

\RX 1 2 3

\ Vowel reproduced . e 5 e e ou e e out e

ifii 1 2 3 34

\ Vowel reproduced . e o e e o e e a e e a$ e

iRt ..... . 1 H 2

} Vowel reproduced . dee ou e e out e e

( 7?x 1 2 3

\ Vowel reproduced . odd ou 6 a ou$ a e

{Rt 1 2 3

( Vowel reproduced . odd d ou a ode

i /?! 1 2 3

( Vowel reproduced . add a d ou a$ o out

(i?! 1 2 3

( Vowel reproduced . d e al 6 ou e dt& d ou$ e i a$ o

tfli 1 2 3

j Vowel reproduced . 6 a i o e ouatioe out atttde

\BX 1 2 3

( Vowel reproduced . 0 d a e i d ou at e i d out at I ut

In addition to what has already been said as to the conventional
signs used by us to indicate the different vowel sounds, it should
be stated that in the preceding tables and subsequent pages a J
following a vowel indicates a rise in its characteristic note, gen-
erally with an accompanying nasal quality. Thus in (1), (2),
(12), and elsewhere, the sound denoted by ou% is nasal. In (1)
it approaches a nasal a. In (13) and elsewhere, the sound de-
noted by a% lies between a and e, and closely approaches or
even passes into the French nasal in. The sound a§ in (18) ap-
proaches i. The sound jj? in (18) is strongly nasal in quality. The
w# in (20), however, is not at all nasal, but is a very high u with
a resonance note much higher than that of t.

276 PROCEEDINGS OF THE AMERICAN ACADEMY

Several series of experiments were also tried in which a number
of vowel sounds in succession were impressed upon the cylinder,
and subsequently reproduced at different speeds, — a method
which enables one to compare more readily the changes in the
various vowels with one another. The results of these compari-
sons are found in Table II.

A careful comparison of the various changes indicated in the
preceding tables will show a close accordance between the results
of different experiments. But there will be noticed a few apparent
discrepancies. Thus in (15) 5 rises to ou% and in (16) to a ; in
(15) o rises to a, and in (16) to o, while a rises to e in both series.
These and such other like results as exist are due chiefly to the fact
that it was difficult to measure the speed with any great exactness
at the higher rates, or to maintain this speed absolutely uniform,
and a slight increase in speed would suffice to change the results
as stated in (15) to those of (16). The vowel a sustains the same
change in each, notwithstanding this difference in speed, because
the e into which it changes is more persistent than the other vowels
in the series, as will be more fully explained a little later. It will
also be instructive to compare (16) with (17). The a in the former
rises to e on passing from one to three revolutions, while in the
latter it rises only to a#, which sound would have passed into e
on a slight increase of speed. In (16) the speed was doubtless a
trifle higher than in (17) as well as in (15).

It must also be remembered that at certain stages a sound will
be on the point of passing from one recognized vowel into another,
so that it may be difficult to denote its sound exactly by any of the
conventional signs usually employed. For this reason it might be
preferable to substitute the symbols used by Mr. Melville Bell in
his "Visible Speech."

Furthermore, we have noticed in some cases that a very trifling
difference in the quality of the vowel impressed upon the cylinder at
a low speed may cause a decided change in the vowel sound given
out at a considerably higher speed. Thus, the vowel e reproduced
at increased speeds passes into a high I and then into i. But if a
series of e's be spoken into the instrument, it is possible to find a
speed of reproduction such that some of them are heard as i 's and
some as *'s. On raising the speed the Vs tend to rise to i, and on
lowering it the t's tend to fall to 7.

Some interesting peculiarities of different vowels were observed
in the course of our experiments.

OF ARTS AND SCIENCES. 277

It was noticed that, in several cases where the vowel seemed to
have quite lost its peculiar quality, there was nevertheless a cer-
tain reminiscence, so to speak, of its original character remaining.
This appeared to be due to the logographic differences among the
various vowels. Of course, the logographic characteristics of any
vowel are not altered by the speed at which the sound is repro-
duced, so that in many cases we necessarily reproduce a sound with
a characteristic resonance note belonging to one vowel and a logo-
graphic character belonging to another. Where the logographic
character is clearly marked, this may enable one to recognize the
vowel sound originally spoken into the phonograph, even though
the characteristic resonance note is quite changed. This is espe-
cially true when the vowel forms part of a word.

There also appears to be a great difference among different vowels
in what we may call the persistence of their vowel character when
the speed of reproduction is varied. Whereas some, as 6, o, and a,
change their character completely on increasing the speed, say to
double its original rate, others change far less. The vowel e seems
particularly persistent under a large change in speed. With it as
with all vowels there is necessarily a shortening at higher speeds,
as denoted in the tables by a dot placed under the letter; but apart
from this the speed may be varied more than for any other vowel
studied by us before any marked change in its quality appears.

In order to form some estimate of the extent to which the context
would influence the judgment as to the character of a vowel sound,
the experiment was tried of reproducing at different speeds a sen-
tence or verse spoken into the instrument. Thus the words from
a negro melody containing the vowel o many times repeated were
spoken, as follows : —

"Roll, Jordan, roll !
Roll, Jordan, roll !
I want to go to heaven when I die
To hear old Jordan roll."

These words were impressed upon the cylinder at a speed of three
revolutions per second, and were reproduced at speeds of two revo-
lutions and one revolution per second respectively, with the follow-
ing results. At two revolutions the o's were in all cases plainly
recognizable though lengthened; but at one revolution the qual-
ity was completely altered, o having become changed to 6 in all
cases. Like results were observed in other sentences containing
the vowel 6.

278 PROCEEDINGS OF THE AMERICAN ACADEMY

In like manner the sentence "This was the noblest Roman of
them all " was impressed upon the cylinder at a speed of one revo-
lution. Reproduced at two revolutions, the o's had a sound which
closely approached u. Lowering the speed slightly changed it to
a very short 5 ; and raising the speed slightly, to a clear u. At
three revolutions the quality of all the vowels was so completely
changed that the sentence was entirely unintelligible even to one
knowing what it really was, the rapidity of the speech, as repro-
duced, however, contributing largely to this lack of intelligibility.
To avoid this latter source of difficulty, the same sentence was
spoken into the instrument at a speed of two revolutions, and re-
produced at one revolution and also at three revolutions. At the
lower speed the i in "this " changed to a, so that, the s in "this "
being rather indistinct, the word seemed almost to have changed
to "that." But the o's, while deepened in quality, did not appar-
ently actually change to o. Lowering the speed still more caused
a closer approach to this, but the o quality still seemed to persist.
This was doubtless due in part to the association of the sound with
the word, and in part to the acoustic effects due to logographic
pressure, and to the connection of the vowel with the preceding
consonants. To study these, the same sentence, preceded by four
o's and followed by the same number, was spoken at two revolu-
tions and reproduced at one revolution. The separate o's seemed
to fall to o, and there was likewise a perceptible fall in the same
sounds in the body of the sentence, but these seemed still to retain
their o sound. To test the matter still further, the same sentence
with the o's mispronounced was spoken into the phonograph, at a
speed of one revolution, as follows: "This was the noblest Roman
of them all." On reproducing it at two revolutions the o's changed
to o, and the sentence was clearly heard with the mispronounced
words rectified, and as distinct as if they had been properly pro-
nounced when impressed upon the cylinder, and reproduced with
the same speed of the cylinder as when uttered. Lowering the
speed below one revolution, the 6" sounds became still deeper and
clearer.

As the vowels o and o are more persistent in their character than
some others, a similar experiment to those already described was
tried with the line, " Though the harbor bar be moaning." This
was impressed upon the cylinder at a speed of one revolution per
second. Reproduced at two revolutions, the words " harbor bar " be-
came " harbor bar " (a as in hat), and at three revolutions the a's

OF AHTS AND SCIENCES. 279

in the same words assumed a nasal quality somewhat approaching
the French nasal in.

The further experiment was performed of sounding the five vow-
els a e i o u successively into the cylinder when this made one
revolution per second, and reproducing them at three revolutions.
It was found that the quality of the different vowels was altered
so that they were unrecognizable by one ignorant of the sounds
which had actually been spoken by the voice. The same result
was reached with the vowels a e e o o, and also with 6 5 a e i. The
last mentioned series, which is No. 20 in the tables, was impressed
upon the cylinder at a speed of one revolution, and reproduced at
two and at three revolutions, approximately. At two revolutions
the series seemed to have changed to o ou aff e i, the a% closely
approaching the French nasal in. At three revolutions the sounds
heard were o ou% a% I u%, the a% being a clear nasal in and the wj
a very short u with a high resonance note.

The limitations in speed of the phonograph cylinder, as the
instrument is constructed for practical purposes, have thus far
prevented us from carrying the range of changes in the pitch of
the reproduced sounds as far as is desirable. This defect we pur-
pose to remedy by suitable modifications in the driving gear of the
apparatus. For reasons alread}7' explained, it is also desirable to
measure the relative rates of rotation more accurately than we have
been able to do with the commercial form of the phonograph.

We hope that we may be able to continue this investigation by
a more systematic study of the behavior of the reproduced vowel
sounds, and likewise to consider the effect of changed pitch in
reproduction upon the various consonantal sounds.

In connection with the present subject, it is interesting to con-
sider the unconscious testimony to the existence of different char-
acteristic resonance notes for the different vowels which is given by
various onomatopoetic words. The words used to denote various
sounds form an excellent example, as will appear from the follow-
ing list of a few such words in which the pitch of the sound denoted
is higher as the list proceeds : — boom, gurgle, roll, toll, roar,
slump, thump, crash, smash, crack, snap, bang, jingle, ring, hiss.
It will be observed that the vowels in the later words are those
with higher resonance notes.

Rogers Laboratory of Physics,

May, 1892.

280 PROCEEDINGS OF THE AMERICAN ACADEMY

XXL

CONTRIBUTIONS FROM THE CHEMICAL LABORATORY
OF HARVARD COLLEGE.

THE REACTIONS OF SODIC ALCOHOLATES WITH
TEIBROMTRIKITROBENZOL. *

SECOND PAPER.

By C. Loring Jackson and W. H. Warren.

Presented June 15, 1892.

In our first paper on this subject we described some experiments
which led to the replacement of nitro groups in symmetrical tri-
bromtrinitrobenzol by ethoxy or methoxy radicals. These observa-
tions seemed to us of special interest because the three nitro groups
are in the meta position in this compound, and, so far as we were
aware, no case was known in which a nitro group in this position
to others had been removed from the benzol ring. In fact the so-
called rule of Laubenheimer stated that a nitro group is replaced
only when it is in the ortho position to another. Even with the
halogens cases where a radical in the meta position exercises a loos-
ening effect on another are very rare, the only one which occurs to
us being the conversion of symmetrical tribrombenzol into dibrom-
anisol by the action of sodic methylate.f

Soon after the appearance of our paper C. A. Lobry de Bruyn
published an account t of some experiments with symmetrical trini-
trobeuzol and sodic methylate from which he obtained dinitroanisol,
thus again removing a nitro group in the meta position to others.
At the same time in an interesting discussion § of the replacement
of nitro groups in aromatic compounds he showed that Lauben-
heimer's rule must be abandoned, since para as well as ortho nitro

* The work described in this paper formed part of a thesis presented to the
Faculty of Arts and Sciences of Harvard University for the degree of Doctor
of Philosophy, by W. H. Warren.

t Blau, Monatsh. f. Ch., VII. 630.

t Rec. Trav. Ch. des Pays-Bas, IX. 208. § Ibid., IX. 210.

OF ARTS AND SCIENCES. 281

compounds are attacked by alcoholates and other reagents with the
removal of nitro groups. This publication brought to our notice an
earlier paper* by him, in which he states that by the action of
alcoholic potassic cyanide on metadinitrobenzol one nitro group is
replaced by the ethoxy (or methoxy) radical, but at the same time
an atom of cyanogen is substituted for one atom of hydrogen, giv-
ing as the product C6H3N02OC2H5C]S\ This curious result seems
to have more affinity with the additions of hydrocyanic acid to nitro-
halogen benzols studied by v. Riehter f than to simple substitu-
tion; but nevertheless we have here the replacement of a meta nitro
group by another radical. As Lobry de Bruyn's later work was
published almost simultaneously with ours (although a little later),
and had grown out of his earlier researches, we felt that the study
of substitutions of nitro groups in simple trinitro compounds
should properly belong to him, and after a pleasant correspondence
on the subject it has been agreed that he should follow out this
line of work, while we confine ourselves, so far as the removal of
nitro groups is concerned, to the completion of our study of tri-
bromtrinitrobenzol.

At present, therefore, we know only three meta nitro compounds
from which nitro groups have been removed, dinitrobenzol, sym-
metrical trinitrobenzol, and symmetrical tribromtrinitrobenzol.

Lobry de Bruyn's work shows that the removal of nitro groups
observed by us is caused by the position of these nitro groups, but
the presence of the three meta bromine atoms evidently also has a
loosening effect on the nitro groups, as we have replaced two of
these groups by ethoxy radicals, whereas in the trinitrobenzol only
one was replaced.

In taking up the study of the subject again, we first examined
the action of tribromtrinitrobenzol and sodic ethylate more care-
fully, to see whether the bromine atoms were not also affected by
it, and found that in addition to the tribromnitroresorcine diethyl-
ether there is always formed a quantity of trinitrophloroglucine
triethylether, C6(OC2H5)3(N02)s, melting at 119-120° ; as however
this substance is easily decomposed by sodic hydrate, the amount
of it obtained as such is small, unless special precautions are taken
to exclude atmospheric moisture. When such precautions are not
taken, the trinitrophloroglucine triethylether is converted into the

* Rec. Trav. Ch., II. 205.

f Ber. d. ch. Ges., IV. 465, VII. 1145, VIII. 1418.

232 PROCEEDINGS OF THE AMERICAN ACADEMY

diethylether C6OH(OC2H5)2(K02)3, melting at 89°, or trinitro-
phloroglucine itself, C6(OH)3(N02)3, (which melts at 167° instead
of 158°, the point given by Benedikt,*) and these substances pass
into the aqueous wash-waters as sodium salts. It follows there-
fore that the action of sodic ethylate on tribromtrinitrobenzol con-
sists of the two following reactions, which take place parallel to
each other : —

C6Br8(NOa)8 + 3 NaOC2H5 = C6(OC2H5)3(N02)3 + 3 NaBr.
C6Br3(N02)3 + 2 NaOC2H5 = C6Br,NOa(OC2H6)2 + 2 NaNOr

We observed further, that, if benzol and alcohol were used as the
solvents instead of alcohol alone, more of the phloroglucine ether was
obtained than when the solvent was only alcohol, and this led us to
study the action quantitatively by determining the amounts of sodic
nitrite and bromide formed, when we found that the amount of
nitrite averaged with the benzol and alcohol 33.49 per cent; with
alcohol alone, 45.92 per cent. There was also a difference in the
reverse direction with the sodic bromide, but the percentages of
this obtained under parallel conditions varied so materially that no
careful comparison was possible. The percentages of sodic nitrite
removed were, on the other hand, remarkably constant. We have
not succeeded in finding any satisfactory explanation for this effect
of the presence of benzol in promoting the formation of the trinitro-
phloroglucine triethylether (produced by the first reaction), and di-
minishing the amount of tribromnitroresorcine diethylether formed
by the second reaction given above.

We have also tried the action of several other alcoholates
on tribromtrinitrobenzol, obtaining the following compounds : —
C6Br3N02(OCH3)2, melting at 126°; Cc(OCH3)2OH(N02)3, melt-
ing at 77-78° ; C6(OC3H7)3(N02)8, from normal propyl alcohol,
melting point 109-110°; the corresponding isocompound melting
at 130° ; and C6(OCH2C6H5)3(N02)3, melting at 171°. A quantita-
tive comparison of the amounts of sodic nitrite formed b}T different
alcoholates indicated that the percentage removed diminishes as the
molecular weight of the alcohol increases, but there were several
exceptions to this general rule.

We have also found that sodic ethylate decomposes the triphenyl-
ether of trinitrophloroglucine, converting it into the triethtylether,
while phenol is set free; and that sodic ethylate when heated with

* Ber. d. ch. Ges., XI. 1376.

OP ARTS AND SCIENCES. 283

the tribromnitroresorcine diethylether removes from it two atoms
of bromine which are replaced by hydrogen, so that the product is
bromnitroresorcine diethylether, C6H2BrN02(OC2H5)o, melting at
115°; — an observation which will be of value in discovering the
cause of the strange replacements of bromine by hydrogen so often
found in the course of this work.

PART I.
Action of Sodic Ethtlate on Tribromtrinitrobenzol.

In our earlier paper * on this subject we showed that sodic ethyl-
ate brought about a replacement of two of the nitro groups in
tribromtrinitrobenzol by two ethoxy radicals forming tribromnitro-
resorcine diethylether, C6Br3]Sr02(OC2H5)2, as the principal product
if alcohol was used as the only solvent and the mixture carefully
cooled. There remained, however, several points which needed
more careful examination, especially the effect upon the reaction of
differences of temperature, the effect of using different solvents,
and the source of the sodic bromide which was always formed in
addition to the sodic nitrite. The results of our work on these
subjects are given in the following paragraphs.

The experiments described in our first paper had led us to think
that the tribromnitroresorcine diethylether was formed only when
the mixture of tribromtrinitrobenzol and sodic ethylate was care-
fully cooled. To test the accuracy of this conclusion, we dissolved
some tribromtrinitrobenzol in alcohol and a little benzol with the
aid of heat, and added to the boiling solution in small quantities at
a time enough sodic ethylate to give three molecules of the ethylate
to each molecule of tribromtrinitrobenzol. As soon as all the
ethylate had been added, the bright scarlet solution was allowed to
cool, and then evaporated spontaneously. The aqueous washings
of the residue gave a strong test for a nitrite, and also for a bro-
mide. The portion insoluble in water was purified b}r crystalli-
zation from alcohol until it showed a melting point of 100° (the
tribromnitroresorcine diethylether melts at 101°), when it was
analyzed with the following result : —

0.2076 gr. of the substance gave by the method of Carius
0.2601 gr. of argentic bromide.

* These Proceedings, XXV. 183.

284 PROCEEDINGS OF THE AMERICAN ACADEMY

Calculated forC6Br3N02(OC2H5)2. Found.

Bromine 53.57 53.32

This analysis with the melting point leaves no doubt that the
substance is the expected tribromnitroresorcine diethylether, and
therefore that the temperature of the reaction does not affect the
nature of the principal product. We have accordingly omitted the
cooling in our subsequent preparations of this body, simply allow-
ing the mixture of tribromtrinitrobenzol, sodic ethylate, and alcohol
to stand over night at ordinary temperatures.

The Modification of the Action when Benzol is used as one

of the Solvents.

To study this subject the following experiment was tried.
10 gr. of tribromtrinitrobenzol were dissolved in dry benzol and an
alcoholic solution of the sodic ethylate from 1.5 gr. of sodium added
(these proportions are essentially three atoms of sodium to each
molecule of tribromtrinitrobenzol). The first drop of the solution
of sodic ethylate turned red as it was added, the color fading to
yellow as the drop mixed with the liquid, so that, after all the
ethylate had been added, the liquid had assumed an orange-red
color. No evolution of heat was observed during the reaction. To
make sure that the action was complete, the mixture was allowed to
stand over night in a corked flask at ordinary temperatures, and
then allowed to evaporate spontaneously, after which the residue
was washed with water to remove the soluble salts.

Substances insoluble in Water. — The residue after washing with
water was crystallized repeatedly from alcohol, and in this way a
considerable quantity of the tribromnitroresorcine diethylether melt-
ing at 101° was obtained from the first crystals, while the mother
liquors yielded a smaller quantity of another substance which when
pure melted at 119-120°. This was dried at 100°, and analyzed
with the following results : —

I. 0.2159 gr. of the substance gave on combustion 0.3284 gr. of
carbonic dioxide and 0.0914 gr. of water.
II. 0.2080 gr. of the substance gave 22.5 c.c. of nitrogen at a tem-
perature of 21°, and a pressure of 759.3 mm.

Found.

II.

12.30

Carbon

Calculated for
C6(OC2H,)3(N02)3.

41.75

i.
41.49

Hydrogen

4.35

4.70

Nitrogen

12.17

OP ARTS AND SCIENCES. 285

It contained no bromine. There can be no doubt, therefore, that
the product was the triethylether of trinitrophloroglucine, and that
the formation of this substance produced the sodic bromide which
was always obtained by the action of sodic ethylate on tribromtri-
nitrobenzol.

Properties of Trinitrophloroglucine Triethylether. — This sub-
stance crystallizes in long slender plates, terminated usually by
one plane at a very sharp angle to the sides. These crystals are
often united longitudinally into broader plates, which frequently
have serrated ends, and may reach more than a centimeter in
length and a millimeter in breadth. The color is white, but it
turns brownish on exposure to the air. It melts at 119-120° ; is
soluble in cold ethyl or methyl alcohol, freely soluble in either of
these solvents when hot ; very freely soluble in benzol, chloroform,
or acetone; freely soluble in glacial acetic acid; soluble in carbonic
disulphide; slightly soluble in ligroine; essentially insoluble in
water, whether cold or hot. The three strong acids have no per-
ceptible action on it hot or cold, except that it is dissolved by hot
strong nitric acid, but on dilution it is precipitated unchanged,
to judge by the melting point. We have tried no experiments on
its saponification by the long continued action of acids. A cold
aqueous solution of sodic hydrate had no action upon it, and only a
slight action when heated, but in alcoholic solution sodic hydrate
decomposes it even in the cold, more rapidly when hot, forming a
reddish yellow solution of the sodium salt of a phenol.

In addition to the tribromnitroresorcine diethylether and trini-
trophloroglucine triethylether, we have always obtained from the
crystallization a considerable amount of a substance which accumu-
lated in the mother liquors and separated from its alcoholic solu-
tion as an oil solidifying after standing for some weeks. We have
devoted a great deal of time to the study of this substance, because
it appeared in such quantity that we thought it must be a principal
product of our reaction; but this work has shown that it consists
principally of the products already described, mixed with ven'
little of an oily substance which prevents them from crystallizing
as usual. In a preparation from SO gr. of tribromtrinitrobenzol,
the mother liquors gave 4.3 gr. of the more or less liquid fraction,
but this amount was reduced to 1.2 gr. after removing the trini-
trophloroglucine triethylether completely by treatment with alco-
holic sodic hydrate, and the tribromnitroresorcine diethylether as
nearly as possible by crystallization from alcohol of the mixture

286 PROCEEDINGS OF THE AMERICAN ACADEMY

solidified by standing for several months. All our attempts to free
the oily product completely from the tribromnitroresorcine diethyl-
ether have failed, so that we are unable to give any account of its
composition.

Products soluble in Water. — In purifying the products of the
action of sodic ethylate upon tribromtrinitrobenzol, the aqueous
solution formed by washing the residue from spontaneous evapora-
tion contained a large amount of organic matter, as was indicated
by its orange-red color. In order to determine its nature, the solu-
tion was acidified with dilute sulphuric acid, which gave a precipi-
tate, but did not remove all the organic matter present, since the
filtrate still showed a strong yellow color. This precipitate was
washed with water, in which it is nearly insoluble, until the wash-
ings ceased to show a yellow color, and then purified by converting
it into its sodium salt, filtering the solution, reprecipitating with
dilute sulphuric acid, and finally crystallizing from dilute alcohol
until it showed the constant melting point 89°, when it was dried
in vacuo and analyzed with the following results : —

0.2285 gr. of the substance gave on combustion 0.3145 gr. of car-
bonic dioxide and 0.0817 gr. of water.

Calculated for
C6(OC,H5)„OH(N02)3. Found.

Carbon 37._85 37.53

Hydrogen 3.47 3.97

To confirm these results, a portion of the substance was treated
with an aqueous solution of less than the calculated amount of sodic
hydrate necessary to convert it into the sodium salt, the solution of
the salt was filtered from the unaltered phenol, the filtrate evapo-
rated to dryness, and the residue washed with benzol to remove any
traces of the free phenol which might have dissolved in the water.
It was then dried at 100°, and the sodium salt thus obtained ana-
lyzed with the following results : —

I. 0.1498 gr. of the substance yielded 0.0329 gr. of sodic sul-
phate.
II. 0.2410 gr. of the salt gave 0.0524 gr. of sodic sulphate.

Calculated for Found.

C6(OC„HB)2ONa(NO„)3. I. n.

Sodium 6.78 7.11 7.04

These analyses leive no doubt that the substance is the diethyl-
ether of trinitrophloroglucine. As it has not been described here-
tofore, we add its properties.

OF ARTS AND SCIENCES. 287

Properties of the Dietliylether of Trinitrophloroglucine. — This
substance crystallizes in square-ended rather short prisms, or in
longer flat needles, also usually with square ends, although some-
times instead of this they are very sharp; both forms are fre-
quently arranged in fan-like groups. It has a straw-yellow color,
and melts at 89° . Very freely soluble in ethyl or methyl alcohol,
ether, benzol, glacial acetic acid, chloroform, or acetone; soluble in
carbonic disulphide; very slightly soluble in ligroine; slightly
soluble in cold water, more soluble in hot; dilute alcohol is the best
solvent for it. The three strong acids have no apparent action on
it, hot or cold. Sodic hydrate dissolves it, forming an orange-red
sodium salt, which crystallizes in fine needles. Amnionic hydrate
dissolves it rather slowly, forming a yellow solution. Solutions of
sodic or acid sodic carbonate also dissolve it with evolution of car-
bonic dioxide forming yellow solutions; it is evident, therefore,
that the substance possesses strongly acid properties.

The filtrate from the diethylether of trinitrophloroglucine, which
had changed from red to yellow on acidification, after concentration
on the water bath deposited upon cooling rather ragged thick yellow
needles; but if the evaporation was carried on spontaneously, yellow
hexagonal prisms were obtained, which dissolved in alkalies more
easily than in water, and gave, according to the amount of alkali
used, red or yellow salts, crystallizing in hair-like needles, proper-
ties which indicated that the substance was a polyatomic nitrophe-
nol, probably the trinitrophloroglucine. This substance has been
described by Benedikt * as crystallizing from water in hexagonal
prisms, and melting at 158° ; we accordingly purified our substance
by crystallization from water, but found that it melted as high as
167°. In spite of the want of agreement between this melting
point and that given by Benedikt, the crystalline form and other
properties indicated that the substance was trinitrophloroglucine,
and this was proved to be the case by the following analyses. As
Benedikt found that trinitrophloroglucine contains one molecule of
water of crystallization, we examined our substance for this.

I. 0.7721 gr. of the air-dried substance when heated to a tem-
perature of 105° lost 0.0477 gr.

Calculated for Found.

C6(0H).,(N0,)3H2O. I.

Water 6.45 6.18

* Ber d. ch. Ges., XI. 1376.

288 PROCEEDINGS OF THE AMERICAN ACADEMY

The air-dried substance lost 0.0015 gr. at 56°, and showed a
tendency to sublime at 105°.

II. 0.2126 gr. of the compound dried at 105° gave on combustion
0.2105 gr. of carbonic dioxide and 0.0304 gr. of water.
III. 0.2260 gr. of the compound dried at 105° gave 31.2 c.c. of nitro-
gen at a temperature of 17° and a pressure of 775.8 mm.

Calculated for Found.

C6(OH)3(N02)3. II. in.

Carbon 27.58 27.01*

Hydrogen 1.15 1.59

Nitrogen 16.09 16.37

It is evident from these analyses that the substance is trinitro-
phloroglucine, and therefore it becomes important to explain the very
marked difference between the melting points observed by Benedikt
and by us. We are inclined to ascribe this to the water of crystal-
lization, as the melting point 167° was obtained with the substance
dried at 105° used for analysis, whereas with samples which had
been only air dried (or dried at 50°) we obtained melting points
as low as 160-161°, that is, only 2° or 3° above the 158° obtained
by Benedikt.

In order to determine whether the formation of the trinitrophlo-
roglucine and its diethylether was due to a direct reaction, or to the
secondary reaction on the trinitrophloroglucine triethylether of some
sodic hydrate formed by the moisture of the air acting on the sodic
ethylate, the following experiment was tried. Absolute alcohol made
in the usual way with quick-lime was treated with a small quan-
tity of sodium, and then the unaltered alcohol distilled off from the
sodic alcoholate in a perfectly dry apparatus, which communicated
with the outer air only through a drying tube; to the distillate in
the flask which served as a receiver, a quantity of bright sodium
was added as quickly as possible, after which it was closed at once
with a cork carrying a drying tube. When the reaction was at an
end, and the solution of sodic ethylate had cooled, 5 gr. of dry
tribromtrinitrobenzol were added, and the mixture allowed to stand
over night closed with the cork carrying the drying tube. The
solution, which had turned red, was acidified with dilute sulphuric

* The percentages of carbon and hydrogen are as near to those required by
the formula as could be expected when the difficulty of making a combustion of
this explosive substance is considered.

OP ARTS AND SCIENCES. 289

acid and allowed to evaporate spontaneously, when after purification
it yielded 2 gr. of the triethylether of trinitrophloroglucine in-
stead of 0.12 gr., the usual yield when no special precautions were
taken to exclude atmospheric moisture. It is evident, therefore,
that the trinitrophloroglucine triethylether is formed at first, and
afterward saponified wholly or in part by sodic hydrate produced by
the action of moisture on the sodic ethylate. That most of this
sodic hydrate is formed during the spontaneous evaporation of the
alkaline solution was shown by two experiments, in which the tri-
ethylether of trinitrophloroglucine was treated with a solution of
sodic ethylate, with all the precautions described above, except that
in one of these experiments the alkaline liquid was allowed to evap-
orate spontaneously, when all the triethylether was saponified, the
whole product being soluble in water, whereas in the other, which
was acidified before evaporating, 0.65 gr. of unaltered triethylether
was recovered, 0.7 gr. having been the amount used.

Lobry de Bruyn* has encountered similar difficulties in studying
the action of sodic etlrylate upon the unsymmetrical trinitrobenzol
(1, 2, 4), as in this case considerable quantities of dinitrophenol
were obtained, whereas with sodic methylate the dinitroanisol was
the only organic product.

Experiments with Acetic Ester as the Solvent.

After we had found that the presence of benzol diminished the
tendency of sodic ethylate to replace nitro groups in the tribrom-
trinitrobenzol, we tried some experiments on the action of other
solvents. The choice here however was limited, because there are
so few liquids belonging to a different class from benzol which
have any considerable solvent action on the tribromtrinitrobenzol ;
in fact, acetone and acetic ester were the only ones easily obtained
which fulfilled this condition, and acetone had to be rejected, as
it seemed to take part in the reaction, giving a dark brownish red
solution, very different from the orange-red obtained in all other
cases. This result was not unexpected after the work of Freer, f
published only in the preliminary paper at the time we tried this
experiment, and since we did this work we have seen the paper of
Janovsky, J describing the colors which he obtained by the action of

* Rec. Trav. Chim. des Pays-Bas, IX. 191.

t Am. Chem. Journ., XII. 355; XIII. 308, Freer and Higley ; XIII. 322.

| Ber. d. ch. Ges., 1891, p. 971.

VOL. XXVII. (ft. S. XIX.) 19

290 PROCEEDINGS OF THE AMERICAN ACADEMY

acetone and potassic hydrate on dinitro compounds of the aromatic
series.

In our first experiment with acetic ester we used the commercial
article without specially drying it. The action was carried on in
the usual way, 5 gr. of trihromtrinitrohenzol heing used. The
aqueous washings gave tests for nitrite and bromide, hut the organic
product was found to consist principally of the tribromdinitro-
phenetol melting at 147°, described in our previous paper.* For
greater certainty it was analyzed, with the following results : —

I. 0.2972 gr. of the substance gave by the method of Carius
0.3721 gr. of argentic bromide.
II. 0.2788 gr. of the substance gave 0.3535 gr. of argentic
bromide.

Calculated for

Found.

C6Br3(N02)2OC2HB.

I. II.

Bromine

53.46

53.27 53.96

This experiment called our attention to a subject which we had
already studied without any very definite result, that is, the condi-
tions under which the phenetol C6Br3(N02)2OC2Il5 is formed, rather
than the tribromnitroresorcine diethylether, C6Br3N02(OC2H5)2.
Our previous work had led us to the conclusion that the presence of
a trace of water is favorable to the formation of the phenetol, as
on one occasion when benzol not dried over sodium was used this
substance was obtained, and in the experiment described in our
previous paper which yielded a quantity of the phenetol common
benzol was also used, whereas in all the preparations made by us
with absolute benzol and alcohol not a trace of the phenetol has been
found. On the other hand, in a repetition of the experiment with
common benzol, and in one in which undried benzol and common
instead of absolute alcohol were used only the resorcine ether
CGBr3lSr02(OC2H5)2 was isolated. To test this question still fur-
ther, we repeated the experiment described at the beginning of this
section, using carefully dried acetic ester instead of the commercial
article, and obtained decidedly less of the phenetol with a large
proportion of the tribromnitroresorcine diethylether, thus confirm-
ing, although not absolutely proving, our previous inference that
the presence of a trace of moisture is favorable to the formation of
the phenetol.

* These Proceedings, XXV. 185.

OF ARTS AND SCIENCES. 291

Action when Alcohol is the only Solvent used.

This action has heen already described in our first paper, but
after we had found, as described in the preceding sections, that the
action when benzol was present took place in the two parallel
reactions,

C6Br,(N02), + 3XaOC2H5 = Cfi(OC2H5)3(N02)3 + 3NaBr,
C6Br8(N02)3 + 2 XaOC2H5 = C6Br3N02(OC2H5)2 + 2 NaN02,

it became of interest to determine whether the first of these reactions
took place if alcohol was the only solvent, or whether the action
consisted of the second alone, as we had supposed when we published
our first paper. A very little work was sufficient to prove the
presence of the trinitrophloroglucine triethylether, or the phenols
formed by its saponification, among the products of the reaction
when alcohol was the only solvent, tbus showing that the action in
the two cases is parallel, although the first reaction takes place to
a much more limited extent when alcohol is the only solvent, than
when a mixture of alcohol and benzol is used. Our attempts to de-
termine the relative amounts of the products of each of these two
reactions are described in a later section.

Preparation of Tribromnitroresorcine Diethylether and
Trinitrophloroglucine Tr iethylether.

It follows from what has been said in the preceding sections,
that the best way to prepare tribromnitroresorcine dietlrylether is
to allow tribromtrinitrobenzol (10 parts) to stand in the cold for
twelve hours with an alcoholic solution of sodic ethylate (from 1.5
parts of sodium), then, after the solvent has evaporated spontane-
ously, to wash the residue with water, and after one crystallization
of the insoluble part from alcohol treat it in the cold with an alco-
holic solution of sodic hydrate for about twelve hours to saponify
the trinitrophloroglucine triethylether also present. The sodium
salt thus formed is washed out, and the residue crystallized from
alcohol until it shows the melting point of 101°.

If, on the other hand, trinitrophloroglucine triethylether is to be
prepared, the tribromtrinitrobenzol should be dissolved in anhydrous
benzol (dried with sodium) and the alcoholic solution of sodic ethyl-
ate added to this solution. Every precaution should be taken to
exclude even traces of moisture, and after the twelve hours stand-
ing the solution should be acidified with dilute sulphuric acid

292 PROCEEDINGS OP THE AMERICAN ACADEMY

before allowing it to evaporate spontaneously. The residue, after
washing with water, is purified by crystallization from alcohol,
which separates the two ethers formed by the parallel reactions.

Quantitative Study of the Action of Sodic Ethylate on
Tvibromtrinitrobenzol.

After we had proved that this action takes place in these two
different ways,

C6Br3(N02)3 + 3 NaOC2H5 = C6(OC2H5)3(N02)3 + 3 NaBr,
C6Br8(N02)8 + 2 NaOC2H5 = C6Br3N02(OC2H5)2 + 2 NaN02,

it became of interest to determine the relative extent of each of the
parallel reactions under varying conditions, and the easiest way to
do this was obviously to find the amount of sodic bromide and sodic
nitrite formed, as the first must have proceeded from the reaction
giving the trinitrophloroglucine triethylether, the second from that
producing the tribromnitroresorcine diethylether. In addition to
this we have weighed the amount of organic matter formed, and have
made some not very successful attempts to determine the amount
of its several constituents. The method adopted was the follow-
ing. A weighed quantity of tribromtrinitrobenzol mixed with the
solvent and the ethylate in the proportion of three atoms of sodium
to each molecule stood over night in a corked flask. The liquid was
then allowed to evaporate spontaneously, and the residue washed
thoroughly with water. The weight of the organic matter insoluble
in water was taken, and also that of the aqueous solution which
contained all the sodium salts ; this was then divided into weighed
parts, one of which was acidified with nitric acid, and after filtering
out and weighing the diethylether of trinitrophloroglucine the
amount of sodic bromide it contained was determined with argentic
nitrate. The second portion of the aqueous liquid was used for the
determination of the amount of sodic nitrite, but it was not easy to
find a method which would be applicable in this case. The com-
mon way of determining a nitrite with potassic permanganate was
inadmissible, because of the presence of organic matter. The urea
method in its usual form was also inapplicable because of the pres-
ence of sodic carbonate, but finally by modifying it in the following
way we succeeded in obtaining satisfactory results. The weighed
portion of the solution to be tested, mixed with a sufficient quantity
of urea, was poured into a little flask, and a small test-tube contain-
ing dilute sulphuric acid put into the flask supported in a vertical

OF ARTS AND SCIENCES. 293

position by a piece of platinum wire projecting from its upper end
and resting against the neck of the flask. The apparatus was then
filled with carbonic dioxide from a heated tube containing mag-
nesite, after which by shaking the flask the sulphuric acid was
added to its contents in small quantities at a time, and the nitrogen
given off collected over a solution of potassic hydrate, and measured
in the usual way. It is necessary to heat the flask gently toward
the end of the operation to drive off all the nitrogen. One half
of the nitrogen collected is derived from the sodic nitrite. To test
the accuracy of the method two determinations of the nitrogen in
commercial sodic nitrite were made by it which gave, —

Found.

Nitrogen 18.09 18.11

and as they agreed with each other, and came tolerably near to the
usual percentage of nitrogen in commercial sodic nitrite (between
19 and 20 per cent), it was evident that the method was accurate
enough for our purposes. A third portion of the aqueous liquid
was in two experiments used for the determination of the trini-
trophloroglucine, but we give our results with a great deal of hesi-
tation, as we were unable to find any satisfactory quantitative
method; methods based upon extraction with an organic solvent,
or the precipitation of the barium salt, which Benedikt says is in-
soluble, led to no result. We were therefore driven to determining
the amount of nitrogen in the residue obtained by evaporating to
dryness a portion of the aqueous solution acidified with sulphuric
acid, and calculating from this the amount of trinitrophloroglucine,
on the assumption, which at best can be but approximately correct,
that this was the only substance containing nitrogen left in the
residue.

Experiments in ivhich Alcohol was the only Solvent used. —
I. Weight taken, 10.556 gr. Weight of aqueous solution, 135.4 gr. ;
8.6 gr. of the solution gave 16.9 c.c. of nitrogen from the sodic
nitrite under a temperature of 23° and a pressure of 763.8 mm. ;
28.2 gr. of the solution gave 1.1718 gr. of argentic bromide ;
20.8 gr. of the solution gave after the nitrous acid had been ex-
pelled by sulphuric acid 8.2 c.c. of nitrogen at a temperature of
23° and a pressure of 767.8 mm.; 54.4 gr. of the solution gave
0.808 gr. of the diethylether of trinitrophloroglucine. The organic
matter insoluble in water weighed 6.97 gr.

II. Weight taken, 10.1582 gr. Weight of aqueous solution, ,
164.55 gr.; 15.95 gr. of the solution gave 24.65 c. c. of nitrogen

294 PROCEEDINGS OP THE AMERICAN ACADEMY

from the sodic nitrite at a temperature of 26°. 5, and a pressure of
765 mm. ; 58.45 gr. of the solution gave 1.6583 gr. of argentic bro-
mide, and yielded 0.8499 gr. of the diethylether of trinitrophloro-
glucine. The organic matter insoluble in water weighed 5.78 gr.

III. Weight taken, 1.0366 gr. Weight of aqueous solution,

121.4 gr. ; 62.5 gr. of the solution gave 13.6 c. c. of nitrogen
from the sodic nitrite at a temperature of 21° and a pressure of
765.2 mm. ; 58.9 gr. of the solution gave 0.2700 gr. of argentic
bromide. The organic matter insoluble in water weighed 0.48 gr.

IV. Weight taken, 10 gr.* Weight of aqueous solution 142.9 gr. ;
13.7 gr. of the solution gave 25.7 c.c. of nitrogen from the sodic
nitrite at a temperature of 29°. 5 and a pressure of 759.2 mm.;
55.1 gr. of the solution gave 1.9029 gr. of argentic bromide; 1.7 gr.
of the diethylether of trinitrophloroglucine were obtained from the
10 gr. used. The weight of organic matter insoluble in water was
6.4 gr.

V. Weight taken, 10 gr.* Weight of aqueous solution, 114.8 gr. ;
14.6 gr. of the solution gave 32.3 c.c. of nitrogen from the sodic
nitrite at a temperature of 28° and a pressure of 764.1 mm. ; 48.7 gr.
of the solution gave 0.9573 gr. of argentic bromide; 2.4 gr. of the
diethylether of trinitrophloroglucine were obtained from the 10 gr.
used. The weight of organic matter insoluble in water was 5.6 gr.

The results of these experiments are given in tabular form at the
end of the next section.

Experiments in which Benzol was the Principal Solvent used. —
VI. Weight taken, 10.0220 gr. Weight of aqueous solution,
126.65 gr. ; 11.7 gr. of the solution gave 17.15 c. c. of nitrogen
from the sodic nitrite at a temperature of 24° and a pressure of

764.5 mm.; 28.7 gr. of the solution gave 1.6952 gr. of argentic
bromide; 24.7 gr. of the solution gave after the nitrous acid had
been expelled by sulphuric acid 12.2 c. c. of nitrogen at a temper-
ature of 25° and a pressure of 766.1 mm. The acid precipitated
from these 24.7 gr. of the solution 0.3374 gr. of the diethylether
of trinitrophloroglucine. The organic matter insoluble in water
weighed 4.99 gr.

VII. Weight taken, 10.1976 gr. Weight of aqueous solution,
135.2 gr. ; 19.3 gr. of the solution gave 27.2 c.c. of nitrogen
from the sodic nitrite at a temperature of 25° and a pressure of
750.9 mm.; 43.9 gr. of the solution gave 1.6158 gr. of argentic

* This weight is accurate only to tenths of a gram.

OF ARTS AND SCIENCES.

295

bromide; 72 gr. of the solution gave 1.4724 gr. of the diethylether
of trinitrophloroglucine. The organic matter insoluble in water
weighed 5.51 gr.

VIII. Weight taken, 1.2524 gr. Weight of aqueous solution,

37.3 gr. ; 24.2 gr. of the solution gave 14.3 c.c. of nitrogen from the
sodic nitrite at a temperature of 19° and a pressure of 771.5 mm. ;
13.1 gr. of the solution gave 0.4097 gr. of argentic bromide. The
organic matter insoluble in water weighed 0.55 gr.

IX. Weight taken, 1.2682 gr. Weight of the aqueous solution,
38.1 gr. ; 19.7 gr. of the solution gave 12 c.c. of nitrogen from the
sodic nitrite at a temperature of 24° and a pressure of 767.3 mm. ;

18.4 gr. of the solution gave 0.5082 gr. of argentic bromide. The
organic matter insoluble in water weighed 0.58 gr.

X. Weight taken, 1.2287 gr. Weight of the aqueous solution,
53.65 gr. ; 17.65 gr. of the solution gave 7.7 c. c. of nitrogen from
the sodic nitrite at a temperature of 25° and a pressure of
766.1mm.; 18.9 gr. of the solution gave 0.2664 gr. of argentic
bromide, and 0.0854 gr. of the diethylether of trinitrophloroglu-
cine. The organic matter insoluble in water weighed 0.68 gr.

In the following tables the first column gives the number of the
experiment, and the weight of tribromtrinitrobenzol used; the sec-
ond, the percentage of nitrogen removed as sodic nitrite referred to
the total amount of nitrogen which could be removed from the tri-
bromtrinitrobenzol by this reaction, that is, two out of the three
atoms of nitrogen, because the product C6Br3N02(OC2H5)2 contains
one nitro group; the third column gives the percentage of the total
bromine removed as sodic bromide; the fourth, the weight of the
organic matter insoluble in water; the fifth, the weight of the di-
ethylether of trinitrophloroglucine; and the sixth, the weight of
trinitrophoroglucine calculated from the volume of nitrogen ob-
tained from the residue after acidification with sulphuric acid.

TABLE I.—

Action of Sodic Ethylate in Ethyl Alcohol.

Weight of

C6Br,(N02)3

used.

Per Cent
of

Nitrogen.

Per Cent

of
Bromine.

Weight of
Organic
Matter.

Weight of
C6(OC2H,)2OH
(N02)3

Weight
of

C6(0H)3(N02\

0.38

I.

10.556

45.88

42.53

6.97

2.0

II.

10.1582

44.85

36.67

5.78

2.39

III.

1.0366

46.95

42.85

0.48

IV.

10.

46.86

39.39

6.4

1.7

V.

10.

45.06

18.02

5.6

2.4

296

PROCEEDINGS OP THE AMERICAN ACADEMY

TABLE II. — Action of Sodic Ethtlate with Benzol and Alcohol.

Weight
of

C6Br3(N02)3

Per Cent
of

Nitrogen.

Per Cent

of
Bromine.

Weight of
Organic
Matter.

Weight of

C6(0C2H5),0H

(N02)3

Weight
of

C6(OH)3(N02)3

VI.

10.022

33.58

59.54

4.99

1.73

0.44

VII.

10.1976

33.09

38.91

5.51

2.8

VIII.

1.2524

33.03

74.32

0 55

IX.

1.2682

33.31

66.21

0.58

X.

1.2287

34.42

49.10

0.68

An examination of these tables shows that the percentages of
nitrogen removed are fairly constant under each set of conditions,
the maximum differences being, in Table I., 2.1 per cent, in Table
II., 1.39 per cent, — which are surprisingly small when the nature of
the process and the roughness of the manipulations are considered.
These numbers, therefore, are well fitted to give an idea of the ef-
fect on the reactions of the presence of benzol, and they show that
it diminishes the amount of sodic nitrite formed, since the percent-
age of nitrogen removed when alcohol alone is present averages
45.92 (maximum 46.95, minimum 44.85), whereas if the solvent is
partly benzol the average percentage falls to 33.49 (maximum 34.42,
minimum 33.03).

On the other hand, no agreement is found in the amounts of
bromine removed as sodic bromide, the maximum difference in
Table I. being 24.83 per cent, in Table II. 35.41 percent; but in
spite of this these results show that the presence of benzol favors the
removal of bromine, since of the five determinations of bromine in
presence of benzol (Table II.), only one (38.91 per cent) is below
the largest percentage of bromine obtained (42.85 per cent) when
alcohol was the only solvent (Table I.), and most of those in Table
II. are very far above those in Table I.

As to the numerical relations between the percentages of inor-
ganic compounds formed under the two sets of conditions, it is to be
observed that in the alcohol series the amounts of nitrite and bro-
mide are approximately equal. In the benzol series the amount of
nitrite is almost exactly one third of the total amount which could
have been formed, and is in some cases about one half that of the

OF ARTS AND SCIENCES. 297

bromide. In most cases, between 80 and 90 per cent of the tribrom-
trinitrobenzol used is accounted for by the amounts of inorganic
salts formed. The experimental work is not accurate enough to
allow a more careful discussion of this part of the subject, as not
enough attention was paid to various details, such, for instance, as
maintaining a constant temperature, and measuring accurately the
amounts of solvent used.

In all the experiments with benzol given in Table II. free alco-
hol was also present. To determine what influence this had on the
reaction, we made another experiment, in which all free alcohol was
carefully excluded, so that in this case benzol was the only liquid
present.

XI. Weight taken, 5.0453 gr. Weight of the aqueous solution,
83.4 gr. ; 19.6 gr. of the solution gave 23.8 c. c. of nitrogen at a
temperature of 28°. 5 and a pressure of 760.1 mm. ; 43.4 gr. of the
solution gave 1.9610 gr. of argentic bromide and 1.55 gr. of the di-
ethylether of trinitrophloroglucine. The organic matter insoluble
in water weighed 2.75 gr.

From these results 35.34 per cent of nitrogen and 59.62 per
cent of bromine are obtained. The percentage of nitrogen, when
benzol and alcohol were used- as the solvents, averaged 33.49, so
that this experiment shows that the presence of alcohol does not
materially affect the result. The somewhat high percentage of
nitrogen in this experiment may be due to the fact that the mix-
ture stood two days instead of the usual twelve hours. This subject
of the effect of time on the action will be discussed later in the
paper.

We have also made two quantitative determinations, in which
acetic ester was used with a little alcohol as the solvent.

XII. Weight taken, 1.0412 gr. Weight of the aqueous solution,
58 gr. ; 17.5 gr. of the solution gave 0.63 c.c. of nitrogen at a tem-
perature of 23°. 5 and a pressure of 758.9 mm.; 40.5 gr. of the
solution gave 0.4504 gr. of argentic bromide.

XIII. Weight taken, 1.0271 gr. Weight of the aqueous solu-
tion, 49.1 gr. ; 18 gr. of the solution gave 2.8 c.c. of nitrogen at a
temperature of 22°. 5 and a pressure of 760.8 mm. ; 31.1 gr. of the
solution gave 0.4902 gr. of argentic bromide.

Per Cent of Nitrogen.

Per Cent of Bromine.

XII. 1.0412

3.62

50.06

XIII. 1.0271

13.49

60.15

298 PROCEEDINGS OF THE AMERICAN ACADEMY

We are inclined to regard No. XII. with suspicion; but No. XIII.
alone shows that acetic ester has an even more unfavorable influence
than benzol on the formation of the sodic nitrite ; this is probably
due to the fact that in this case there is a tendency to form the tri-
bromdinitrophenetol, which would yield half as much sodic nitrite
as the tribrommononitroresorcine diethylether formed when benzol
was used.

Relative Yields of the Organic Products. — After we had deter-
mined the amounts of sodic bromide and nitrite formed by the two
parallel reactions,

C6Br3(N02)3 + 3 NaOC2H5 = C6(OC2H5)3(N02)3 + 3 NaBr,
C6Br3(N02)3 + 2 NaOC2H5 = C6Br3N02(OC2H5)2 + 2 NaN03,

we tried to get an idea of the relative yields of the organic products.
This could be done with some approach to accuracy in the case of
the reaction which produces sodic bromide, because during tbe work
most of the trinitrophloroglucine trietbylether was converted into
the salts of trinitrophloroglucine or its diethylether, both of which
can be easily separated from the other organic products on account
of their solubility in water. With the tribromnitroresorcine di-
ethylether on the other hand, no such approach to accuracy was
obtained, because it could be purified only by crystallization, and
a large portion of it remained mixed with the viscous impurity
already mentioned. To obtain the following results, the organic
matter insoluble in water obtained from two experiments was re-
peatedly crystallized from alcohol, until as much pure tribromni-
troresorcine diethylether and trinitrophloroglucine triethyletber
had been obtained as possible. To the amount of the latter, which
was very small, were added tbe calculated amounts of the triethyl-
etber corresponding to the quantities found of free trinitrophloro-
glucine and its diethylether. Two pairs of experiments were
studied in this way, one from the series in which alcohol was the
only solvent, and one from that in which benzol was used.

Experiments I. and II — Alcohol the only solvent. 20.71 gr.
of tribromtrinitrobenzol gave 12.75 gr. of organic matter insoluble
in water, from which were obtained 5.11 gr. of C6Br3NO2(0C2H5)2,
1.4 gr. of the same slightly impure, 5.1 gr. of the semi-liquid frac-
tion from the mother liquor, and 0.49 gr. of C6(OC2H5)3(N02)3.
From the aqueous solution 4.39 gr. of C6OH(OC2H5)2(N02)3
were obtained, corresponding to 4.77 gr. of the trietbylether, and

OF ARTS AND SCIENCES. 299

0.78 gr.* of C6(OH)3(N02)3, corresponding to 1.03 gr. of the tri-
ethylether, making the total yield of the triethylether 6.29 gr.

Experiments VI. and VII. — Benzol present, 20.21 gr. of tri-
bromtrinitrobenzol gave 10.50 gr. of organic matter insoluble in
water from which were obtained 3.25 gr. of C6Br3N02(OC2H5)2,
1.36 gr. of C6(OC2H5)3(lSr02)3, and somewhat less than 6 gr. of
the semi-liquid fraction from the mother liquors. From the aque-
ous solution were obtained 4.53 gr. of C6OH(OC2H5)2(lSr02)3,
corresponding to 4.93 gr. of the triethylether, and 0.88 gr.* of
C6(OH)3(iSl"02)3, corresponding to 1.16 gr. of the triethylether,
making the total yield of the triethylether 7.45 gr.

These results confirm the inference drawn from the percentage,
of sodic nitrite and bromide, that the presence of benzol is unfavor-
able to the reaction hj which sodic nitrite is formed, but promotes
that which yields sodic bromide; a fact which is shown more plainly
by this collection of the results in tabular form.

C6(OC2H5)3(N02)3. C6Br3N02(0C2Hs)2

Alcohol alone (I. and II.) 6.29 gr. 5.11f

Benzol and alcohol (VI. and VII.) 7.45 gr. 3.25f

All our results, therefore, show that the presence of benzol is fa-
vorable to the elimination of bromine, unfavorable to that of nitro
groups. The most probable theoretical explanation of this obser-
vation which has occurred to us depends on the effect of the change
of solvents upon the amounts of the salts precipitated, hut any dis-
cussion of this theory at present would not be worth while, because
the principle on which it rests has not been tested by experiment
so far as we can find.

We have not succeeded in finding the cause of the very marked
variations in the amounts of sodic bromide shown in Tables I. and
II. At first we feared they might be due to defects in our experi-
mental work, but that this is not the case is shown by the following
comparison of the weights of trinitrophloroglucine triethylether
actually found with the amounts of this substance calculated from
the percentages of bromine eliminated as sodic bromide in the same
experiment. We have selected this body for the comparison, be-

* These numbers are only estimates, as the amounts of trinitrophloroglucine
were determined only in Nos I. and VI., the weight found being doubled to give
the numbers. It is to be remembered also that our method for determining
the trinitrophloroglucine was far from satisfactory.

t These numbers are only approximations to the true yields.

Calculated

Found

6.30

6.29

7.62

7.45

300 PROCEEDINGS OF THE AMERICAN ACADEMY

cause, as has been already stated, these weights were determined
with a fair degree of accuracy.

Alcohol alone (I. and II.)
Alcohol and benzol (VI. and VII.)

The agreement is much closer than we had any right to expect,
and shows that the differences in the percentages of bromine are
due to absolute variations in the extent of the reaction by which
the bromine is removed, since experiments VI. and VII. differ
in this respect very widely (VI. 59.54 per cent of bromine, VII.
38.91 per cent of bromine); and yet the amount of the trini-
trophloroglucine triethylether calculated from these different per-
centages of bromine corresponds almost exactly to that obtained
experimentally.

PART II.

Action of other Alcoholates on Tribromtrinitrobenzol.

In addition to the work with sodic ethylate just described, we
have tried the action of the sodium compounds of other alcohols on
the tribromtrinitrobenzol, and give in the first place descriptions
of the new confounds thus obtained, followed by a series of quan-
titative experiments similar to those tried with the ethylate.

Sodic Methylate.

The organic compound insoluble in water obtained by the action
of sodic methylate on tribromtrinitrobenzol consisted in every ex-
periment we have tried of the tribromnitroresorcine diinethylether,
melting at 126°, and already described in our first paper;* as,
however, we found that a considerable amount of sodic bromide
was formed in these experiments, we turned our attention to the
aqueous washings of this organic matter, in which it was evident
that the product formed by the removal of the bromine was to be
sought. Upon acidifying this aqueous solution with dilute sul-
phuric acid, a copious precipitate was obtained, which was only
slightly soluble in water, and was purified by crystallization with
the following precautions. The substance was dissolved in as small

* These Proceedings, XXV. 186.

OF ARTS AND SCIENCES. 301

a quantity as possible of cold alcohol, water was then added until
it began to grow turbid, when the solution was cleared by the ad-
dition of a drop or two of alcohol, and allowed to evaporate spon-
taneously, all these operations being carried on in the cold. When
it showed the constant melting point 77-78°, it was dried and
analyzed with the following results : —

0.2298 gr. of the substance gave on combustion 0.2792 gr. of
carbonic dioxide and 0.0597 gr. of water.

Calculated for
C6(0CH3),0H(N02)3. Found.

Carbon 33.22 33.13

Hydrogen 2.42 2.89

To confirm this result the sodium salt was made and analyzed;
for this purpose 1 gr. of the substance was treated with 0.1 gr. of
sodic hydrate dissolved in a little water, that is, decidedly less sodic
hydrate than would be needed to convert the whole of the substance
into its salt. The yellow solution thus obtained was evaporated to
dryness at 100°, washed with benzol to remove the small quantity
of the free phenol which had dissolved in the water, dried at 100°,
and analyzed with the following result: —

0.3730 gr. of the salt gave 0.0874 gr. of sodic sulphate.

Calculated for

C6(0CH3)20Na(N02),.

Found

7.39

7.59

Sodium

These analyses and the analogy with the corresponding ethyl
compound leave no doubt that the substance is the dimethylether
of trinitrophloroglucine.

Properties of the Dimethylether of Trinitrophloroglucine,
C6(OCH3)2OH(N02)3. — The substance crystallizes with the pre-
cautions given above in long slender needles, with a slightly
yellowish tinge, which melt at 77-78°, and are very soluble in ethyl
alcohol, methyl alcohol, ether, benzol, chloroform, acetone, or gla-
cial acetic acid; soluble in carbonic disulphide; slightly soluble in
ligroine; somewhat soluble in cold water, more soluble in hot.
With alkalies it forms reddish yellow salts. Strong sulphuric or
hydrochloric acid does not act on it; it dissolves in strong nitric
acid, but seems to be precipitated unchanged by dilution.

We also obtained a small amount of another substance with a
higher melting point, but not in sufficient quantity to charac-
terize it.

302 PROCEEDINGS OF THE AMERICAN ACADEMY

Action of Sodic Propylate on Tribromtrinitrobenzol.

4 gr. of normal propyl alcohol were mixed with anhydrous ben-
zol, and treated with 1.5 gr. of metallic sodium until all the sodium
had disappeared; the reaction ran slowly, and was assisted by a
gentle heat. The sodic propylate thus obtained was carefully
cooled, and then a benzol solution of 10 gr. of tribromtrinitroben-
zol added in small portions at a time, shaking and cooling with
water after each addition. The proportions are about three atoms
of sodium and three molecules of propyl alcohol to each molecule of
tribromtrinitrobenzol. As the first portions of the solutions were
mixed the liquid turned blood-red, and this color, which at first faded
to yellow on shaking, became permanent as more of the solution of
tribromtrinitrobenzol was added. The mixture, which at no time
showed a rise of temperature, was allowed to stand over night in a
corked flask, and then the solution was filtered from a deposit of
solid matter, which, after drying off the benzol, gave tests for a
bromide and a nitrite. The benzol solution to which the solid not
used for the above tests had been added was treated with water,
and then acidified with dilute sulphuric acid, washed thoroughly,
and, after most of the benzol had been recovered by distillation,
the rest was distilled off in a current of steam. The residue thus
obtained was oily, but solidified after standing for some time; it
was then purified by crystallization from alcohol until it showed the
constant melting point 109-110°, when it was dried at about 70°,
and analyzed with the following results : —

0.2366 gr. of the substance gave on combustion 0.4058 gr. of
carbonic dioxide and 0.1214 gr. of water.

Calculated for
C6(0C3H7);!(N02)3. Found.

Carbon 46.51 46.78

Hydrogen 5.43 5.70

The substance gives no test for bromine when heated on a copper
wire. These results prove that it is the normal propylether of
trinitrophloroglucine.

The aqueous solution, acidified with sulphuric acid, from which
the benzol had been separated gave on extraction with ether a
small amount of a yellow substance, which seemed to be trinitro-
phloroglucine, but was not present in sufficient amount for complete
identification.

OF ARTS AND SCIENCES. 303

Properties of the Normal Tripropylether of Trinitrophloroglucine,
C6(OC3H7)3(N02)3. — This substance crystallizes in plates often
as much as three millimeters long and one broad, which under the
microscope are seen to be made up of a number of flat prisms with
square ends united by their longer sides, and usually much striated
x on lines parallel to both sets of edges. Its color is white with a
very slight yellowish tinge, and it turns yellowish brown on stand-
ing exposed to the air. It melts at 109-110°, and is soluble in
cold ethyl or methyl alcohol, more freely when hot ; freely solu-
ble in ether, benzol, chloroform, acetone, or carbonic clisulphide;
soluble in glacial acetic acid; slightly soluble in ligroine, or in
water whether hot or cold. Neither strong sulphuric, strong nitric,
nor strong hydrochloric acid has any apparent action on it, whether
cold or hot. The best solvent for it is boiling alcohol.

In another experiment no benzol was used, but the tribromtrini-
trobenzol suspended in propyl alcohol was treated with sodic pro-
pylate. The product in this case was an oil which did not solidify
even after standing for three months. We accordingly tried to
purify it by treatment with a cold solution of sodic hydrate, and in
this way obtained an orange solution, from which trinitrophloro-
glucine was easily isolated, pointing to the presence of the tripropyl
ether of this body in the oil. After we could obtain no more of the
sodium salt of the trinitrophloroglucine by further action of sodic
hydrate, the oil was washed with water, dissolved in alcohol, pre-
cipitated again with water, and dried at 100°, when we hoped an
analysis might throw some light on its composition; but in this we
were disappointed, as a determination of the amount of bromine
gave 45.29 per cent, whereas the tribromnitroresorcine dipropyl-
ether, which we hoped might have been formed, should contain
50.42 per cent, of bromine. As we could find no better way of puri-
fying this substance, we have been forced to leave undecided the
nature of the product formed by the replacement of nitro groups
in tribromtrinitrobenzol by propoxy radicals. Fortunately, it is not
a point of great importance.

Action of Sodic Isopropylate on Tribromtrinitrobenzol.

4 gr. of isopropyl alcohol were converted into its sodium com-
pound by treatment with 1.5 gr. of sodium in anhydrous benzol,
when it was found that the isopropyl alcohol acts on sodium more
energetically than normal propyl alcohol, but both act less readily
than ethyl alcohol. The isopropylate thus obtained was allowed to

304 PROCEEDINGS OP THE AMERICAN ACADEMY

act on 10 gr. of tribromtrinitrobenzol under the conditions de-
scribed in the preceding section. The phenomena observed in this
case were the same as those described for the normal propylate ex-
cept that a slight rise of temperature from the reaction was observed.
The solid deposited over night gave a strong test for sodic bromide
and a distinct test for sodic nitrite. The principal organic product
was obtained and purified in the way given under the normal propyl
compound until it showed the constant melting point 130°, when
it was dried at 100°, and analyzed with the following results: —

0.2280 gr. of the substance gave on combustion 0.3876 gr. of car-
bonic dioxide and 0.1182 gr. of water.

Calculated for
C6(OC3H7)3(N02)3. Found.

Carbon 46.51 46.36

Hydrogen 5.43 5.76

The substance gave no test for bromine when heated with cupric
oxide. A small amount of trinitrophloroglucine seemed to be
formed as a secondary product in preparing the substance analyzed
above.

Properties of the Triisopropylether of Trinitrophloroglucine,
C6(OC3H7)3(N02)3. — This substance crystallizes in plates often one
centimeter long, made up of flattened prisms united by their longer
sides. These prisms are terminated by two planes at an obtuse
angle to each other, and seem to belong to the monoclinic system.
It is white when first prepared, but gradually takes on an orange
color on exposure to the air. It melts at 130°, and is not very
soluble in cold ethyl or methyl alcohol, more soluble in hot; very
soluble in benzol or chloroform ; freely in ether, or acetone; soluble
in carbonic disulphide; slightly soluble in cold glacial acetic acid,
freely when hot; very slightly soluble in ligroine, and nearly
insoluble in. water whether cold or hot. The three strong acids
have no apparent action on it whether cold or hot. The best sol-
vent for it is boiling alcohol.

Action of Sodic Benzylate on Tribromtrinitrobenzol.

The sodic benzylate used was prepared as follows. To 1.3 gr. of
sodium mixed with anhydrous benzol and heated in a flask with a
return condenser, 6.5 gr. of benzyl alcohol were added in small
quantities at a time, and the heating continued until all the sodium
had disappeared, which usually was not till after four hours. The

OF ARTS AND SCIENCES. 305

benzyl alcohol therefore acts with sodium much more slowly than
any of the other alcohols used by us. In this way we obtained a
benzol * solution of the sodic benzylate, which remained clear after
it had cooled until it was shaken, when the solid separated in a
gelatinous state. To the mixture of gelatinous sodic benzylate and
benzol thus obtained a benzol solution of 9 gr. of tribromtrinit.ro-
benzol was added ; that is, for each molecule of tribromtrinitroben-
zol we used three molecules of sodic benzylate. f The mixture was
allowed to stand in the cold over night, the orange-red solution thus
formed evaporated to dryness on a steam radiator at temperatures
below 70°, and the residue washed with water and afterward with
alcohol, after which it was purified by crystallization from a mix-
ture of benzol and alcohol, until it showed the constant melting
point 171°. The analyses of the substance dried at 100° gave the
following results : —

I. 0.2038 gr. of the substance gave on combustion 0.4546 gr.
of carbonic dioxide and 0.0752 gr. of water.
II. 0.2678 gr. of the substance gave 18.8 c.c. of nitrogen at a tem-
perature of 25° and a pressure of 765.3 mm.

Calculated for

Found.

C6(OC7H7)3(N02)3.

I. H.

Carbon

61.01

60.84

Hydrogen

3.96

4.10

Nitrogen

7.91

7.8

The substance gave no test for bromine when heated with cupric
oxide.

10 gr. of tribromtrinitrobenzol gave only 1.5 gr. of the tribenzyl-
ether of trinitrophloroglucine, the analysis of which is given above,
that is, less than 13 per cent of the theoretical yield. This sub-
stance, therefore, is not by any means the principal product of the
reaction. What the other products are will be discussed after the
description of the properties of the benzylether.

Properties of the Trinitrophloroglucine Tribenxylether. — This
substance crystallizes from a mixture of alcohol and benzol in slen-

* Since this part of our work was finished, Briilil and Biltz have puhlished
similar observations on other alcoholates in Ber. d. ch. Ges., XXI. 649 (1891).

t The same principal product was obtained in a subsequent experiment with
only two molecules of sodic benzylate. In most cases a slight excess of benzyl
alcohol was used.

vol. xxvii. (x. s. xix.) 20

306 PROCEEDINGS OF THE AMERICAN ACADEMY

der white needles forming a thick mat. It turns yellowish brown
on exposure to the air, and melts at 171° ; is slightly soluble even
in hot alcohol, less soluble still in cold; somewhat more soluble in
methyl than in ethyl alcohol; very freely soluble in benzol, chloro-
form, or acetone; freely in carbonic disulphide; soluble in glacial
acetic acid; very slightly soluble in ligroine; essentially insoluble
in water, whether cold or hot. The best solvent for it is a mixture
of alcohol and benzol. Strong sulphuric acid does not seem to act
on it until charring sets in ; strong nitric acid does not act on it
in the cold, but seems to oxidize it when hot; strong hydrochloric
acid has no apparent action on it, hot or cold.

Other Products of the Action of Sodic Benzylate on Tribromtri-
nltrobenzol. — To obtain these substances the aqueous and alcoholic
washings mentioned above were evaporated to dryness, and the oil}'
portion separated by extraction with a little alcohol from the salts.
These, it was found, wrere a mixture of the sodium salt of trinitro-
phloroglucine with sodic bromide and nitrite, from which the trini-
trophloroglucine was easily obtained, and identified by the melting
point 167°, and by analysis. It is one of the principal products of
the reaction, and in fact most of the trinitrophloroglucine used for
the analyses given in the first part of this paper was obtained in
this way.

The oily material separated by the alcohol consisted mostly of
the excess of benzyl alcohol, but on warming it we perceived the
smell of benzyl bromide, and also suffered from its violent action on
the eyes. Accordingly some of it, carefully washed to remove any
sodic bromide, was boiled with an alcoholic solution of sodic sul-
phide, when it gave a strong smell of benzyl sulphide, and the
water with which it was washed gave a faint test for bromine with
chlorine water. We did not succeed, however, in isolating the
benzyl sulphide, which at best must have been present in very small
quantity. Another similar oil, after thorough washing with water,
was boiled with sodic acetate and alcohol, then water was added,
which after being freed from the organic matter gave a slight test for
bromine with chlorine water. In another experiment the original
product, after acidification with dilute sulphuric acid, was distilled
with steam, and the oily distillate, having been thoroughly washed
with water, was boiled with alcoholic sodic acetate, when it yielded
a very strong test for a bromide with chlorine water. These exper-
iments have convinced us that in these three preparations a small
quantity of benzyl bromide was present in the product of the reac-

OF ARTS AND SCIENCES. 307

tion, although we have not succeeded in isolating the benzyl bro-
mide itself, or one of its derivatives. This did not proceed from an
impurity of benzyl bromide in the benzyl alcohol used, since after
boiling it with an alcoholic solution of sodic acetate no test for so-
dic bromide could be obtained ; it must have been formed, therefore,
either in the course of the reaction, or in the subsequent processes
of purification. It is barely possible that this latter supposition
may account for it in the last case, where the strongest test for
bromine was obtained, as this was acidified before distillation with
steam, and hydrobromic acid produced by the sulphuric acid and
sodic bromide might have converted some of the excess of benzyl
alcohol into benzyl bromide, although this seems highly improbable,
because the solution was kept throughout in a very dilute state.
In the two previous cases, however, this explanation cannot apply.
as no acid whatever had been added, so that no hj'drobromic acid
could have been formed; we are forced therefore to assume that the
benzyl bromide was formed by the direct reaction and not bjr a sec-
ondary one, and under these circumstances the following reaction
is the only one which seems to us admissible :

3 C7H7OXa + C6Brs(N02)3 = C6(ONa)3(N02)3 + 3 C7H7Br.

This is certainly very improbable, and we should add, that, when
we tried to confirm it by a repetition of the experiment, we did not
succeed in detecting any benzyl bromide in the product. At first
sight it would seem that a reaction the reverse of that given above
would be more probable, but we proved that this was not the case
by a special experiment, which showed that benzyl bromide had no
action on the sodium salt of trinitrophloroglucine under the condi-
tions used by us. We may add that amyl bromide also has no action
under these conditions. On the other hand, there is little doubt
that the benzyl bromide, if formed by this reaction, would act on
the sodic benzylate forming benzylether. Accordingly, we tried to
isolate benzylether from the oily product of the reaction by distil-
ling off the excess of benzyl alcohol; there was so little of the resi-
due which did not pass over at 207° that it was impossible to purify
it properly; such as it was, however, it gave results on analysis
agreeing with those calculated for benzyl alcohol (carbon 76.70
instead of 77.78). We conclude, therefore, that if the reaction given
above takes place, it is only to a very moderate extent, the principal
reaction being the formation of the trinitrophloroglucine tribenzyl-
ether, which was then more or less saponified by the sodic hydrate

308 PROCEEDINGS OF THE AMERICAN ACADEMY

formed by the action of atmospheric moisture on the sodic benzyl-
ate. We have not succeeded in detecting the organic substance
formed by the removal of one or more nitro groups, as indicated by
the appearance of sodic nitrite among the products.

Sodic Isobutylate or Sodic Isoamylate acted with tribromtrinitro-
benzol in the same way as the alcoholates already mentioned, but
the organic products insoluble in water were oily, and we did not
succeed in isolating any compounds fit for analysis from them.
The aqueous filtrates contained a considerable amount of the so-
dium salt of trinitrophloroglucine. As the subject was not of
sufficient interest to repay extended work, it was abandoned.

Quantitative Study of the Action of other Alcoholates on
Tribromtrinitrobenzol.

The object of this work was to make a comparison between the
actions of sodic ethylate and of other alcoholates on tribromtrini-
trobenzol, and for this purpose we selected the quantitative de-
termination of the amounts of sodic nitrite formed by the reaction,
since our results with the ethylate had shown that the percentage
of nitrogen removed as sodic nitrite was essentially constant under
the conditions used by us. The amount of bromide formed was
also determined in most cases, although of little value for pur-
poses of comparison. Accordingly the following determinations
were made, the results of which, with those from sodic ethylate al-
ready described, are given together in tabular form after the de-
scriptions of the determinations. To economize our alcohols, as we
had but a small stock of some of them, we have used principally the
method with benzol as a solvent.

Experiments in which the Alcohol was the only Solvent.

XIV. "Weight taken. 1.0578 gr. Alcoholate used, sodic methyl-
ate. Weight of aqueous solution, 115.1 gr. 54.3 gr. of the solution
gave 13.6 c.c. of nitrogen from the sodic nitrite at a temperature
of 18° and a pressure of 758.9 mm. 60.8 gr. of the solution gave
0.3768 gr. of argentic bromide.

XV. Weight taken, 1.157 gr. Alcoholate used, sodic propylate.
Weight of aqueous solution, 92 gr. 54.1 gr. of this solution gave
13.8 c.c. of nitrogen from the sodic nitrite at a temperature of
16° and a pressure of 775.4 mm.

XVI. Weight taken, 1.1582 gr. Alcoholate used, sodic isobu-
tylate. Weight of aqueous solution, 117.5 gr. 33.1 gr. of the solu-

OF ARTS AND SCIENCES. 309

tion gave 5.25 c.c. of nitrogen from the sodic nitrite at a tempera-
ture of 16° and a pressure of 7C5.5 mm. 43.3 gr. of the solution
gave 0.2390 gr. of argentic bromide.

XVII. Weight taken, 1.2696 gr. Alcoholate used, sodic iso-
butylate. Weight of aqueous solution, 56.65 gr. 19.3 gr. of the
solution gave 9.4 c.c. of nitrogen from the sodic nitrite at a tem-
perature of 29°. 5 and a pressure of 756.3 mm. 15.95 gr. of the
solution gave 0.2198 gr. of argentic bromide.

XVIII. Weight taken, 1.5118 gr. Alcoholate used, sodic iso-
amylate. Weight of aqueous solution, 53.3 gr. 26.5 gr. of the solu-
tion gave 8.4 c.c. of nitrogen from the sodic nitrite at a tempera-
ture of 20° and a pressure of 762.4 mm. 26.25 gr. of the solution
gave 0.3352 gr. of argentic bromide.

XIX. Weight taken, 1.5656 gr. Alcoholate used, sodic isoamyl-
ate. Weight of aqueous solution 85.1 gr. 37.4 gr. of the solution
gave 9.9 c.c. of nitrogen from the sodic nitrite at a temperature of
19°. 5 and a pressure of 766.2 mm.

Action of Sodic Methylate in Benzol.

XX. Weight taken, 1.0892 gr. Weight of solution, 65.7 gr.
31.7 gr. gave 10.1 c.c. of nitrogen from sodic nitrite at a tempera-
ture of 22° and a pressure of 766.9 mm. 34 gr. gave 0.4212 gr. of
argentic bromide. The organic matter insoluble in water weighed
0.509 gr.

XXI. Weight taken, 1.2612 gr. Weight of aqueous solution,
40.05 gr. 17.35 gr. of the solution gave 11.7 c.c. of nitrogen from
the sodic nitrite at a temperature of 25° and a pressure of 758.9 mm.
22.7 gr. of the solution gave 0.4088 gr. of argentic bromide.

XXII. Weight taken, 1.1561 gr. Weight of aqueous solution,
58.9 gr. 24.3 gr. of the solution gave 10.9 c.c. of nitrogen from
the sodic nitrite at a temperature of 25°. 5 and a pressure of
765.4 mm. 34.6 gr. of the solution gave 0.4732 gr. of argentic
bromide.

Action of Normal Sodic Propylate in Benzol.

XXIII. Weight taken, 1.2281 gr. Weight of aqueous solution,
60.85 gr. 22.75 gr. of the solution gave 8.2 c.c. of nitrogen
from the sodic nitrite at a temperature of 20°. 5 and a pressure of
759.4 mm. 38.1 gr. of the solution gave 0.1398 gr. of argentic
bromide.

310 PROCEEDINGS OF THE AMERICAN ACADEMY

XXIV. Weight taken, 1.297 gr. Weight of aqueous solution,
71.6 gr. 19.6 gr. of the solution gave 4.6 c.c. of nitrogen
from the sodic nitrite at a temperature of 30° and a pressure of
767 mm. 52 gr. of the solution gave 0.7827 gr. of argentic
bromide.

Action of /Sodic Isopropylate in Benzol.

XXV. Weight taken, 1.3434 gr. Weight of aqueous solution,
50.15 gr. 20 gr. of the solution gave 5.9 c.c. of nitrogen from
the sodic nitrite at a temperature of 24°. 5 and a pressure of
762.5 mm. 30.15 gr. of the solution gave 0.2679 gr. of argentic
bromide.

Action of Sodic Isobutylate in Benzol.

XXVI. Weight taken, 1.1598 gr. Weight of aqueous solu-
tion, 59.05 gr. 27.05 gr. of the solution gave 5.2 c.c. of nitrogen
from the sodic nitrite at a temperature of 23°. 5 and a pressure of
759.2 mm. 32 gr. of the solution gave 0.303 gr. of argentic
bromide.

XXVII. Weight taken, 1.1551 gr. Weight of aqueous solu-
tion, 79.5 gr. 22.05 gr. of the solution gave 4.2 c.c. of nitrogen
from the sodic nitrite at a temperature of 27° and a pressure of
764.5 mm. 57.45 gr. of the solution gave 0.722 gr. of argentic
bromide.

Action of Sodic Isoamylate in Benzol.

XXVIII. Weight taken, 1.4427 gr. Weight of aqueous solu-
tion, 85.55 gr. 31.7 gr. of the solution gave 5.7 c.c. of nitrogen
from the sodic nitrite at a temperature of 23° and a pressure of
760.9 mm. 40.65 gr. of the solution gave 0.4184 gr. of argentic
bromide.

XXIX. Weight taken, 1.4485 gr. Weight of aqueous solution,
106.65 gr. 33.6 gr. of the solution gave 5.3 c.c. of nitrogen
from the sodic nitrite at a temperature of 25°. 5 and a pressure of
764.2 mm. 73.05 gr. of the solution gave 0.8515 gr. of argentic
bromide.

Action of Sodic Benzylate in Benzol.

XXX. Weight taken, 1.0747 gr. Weight of aqueous solution,
92.2 gr. 33.5 gr. of the solution gave 2.7 c.c. of nitrogen from
the sodic nitrite at a temperature of 30°. 5 and a pressure of

OF ARTS AND SCIENCES.

311

758.8 nun. 58.7 gr. of the solution gave 0.5584 gr. of argentic
bromide.

Action of Sodic Phenylate in Benzol.

XXXI. Weight taken, 1.1227 gr. Weight of aqueous solution,
67.15 gr. 32.5 gr. of the solution gave 3 c.c. of nitrogen from
the sodic nitrite at a temperature of 29° and a pressure of
766.5 mm. 30.05 gr. of the solution gave 0.1568 gr. of argentic
bromide.

The results of these experiments are collected in Tables III. and
IV. with those previously given by sodic ethylate. The first column
contains the sort of alcohol used and the number of the experi-
ment, the second the weight of tribromtrinitrobenzol used, the
third the percentage of nitrogen, and the fourth the percentage
of bromine removed, calculated in the way already described in
connection with Tables I. and II.

TABLE III. — ExPERIMtNTS WITH THE ALCOHOL ALONE.

Sort of Alcohol used

Weight of

Tribrouitrinitro-

benzol.

Percentage
of

Nitrogen

j

Percentage

of
Bromine.

Methyl XIV.

1.0578

50 52

53.79

Ethyl I.

10.556

45.88

42.53

II.

10.1582

44.85

3667

III.

1.0366

46.95

42.85

IV.

10.

46.86

39.39

V.

10.

45.06

18.02

Propyl XV.

1.157

38.80

Isobutyl XVI.

1.1582

30.40

44.69

XVII.

1.2696

37.83

49.04

Isoamyl XVIII.

1.5118

20.62

36.16

XIX.

1.5656

26.73

312

PROCEEDINGS OF THE AMERICAN ACADEMY

TABLE IV. — Experiments with Alcohol and Benzol.

Sort of Alcohol used

Weight of

Tribromtrinitro-

benzol.

Percentage
of

Nitrogen.

Percentage

of
Bromine.

Methyl XX.

1.089

35.28

59.62

XXI

1.261

3837

45.64

XXII.

1.156

41 17

55.59

Ethyl VI.

10.022

33.58

59.54

VII

10.1976

33.09

38.91

VIII

1.2521

33 03

74.32

IX

1.2082

33.31

66.21

X.

1.2287

34.42

49.10

Propyl XXIII.

1.2281

32.74

14.51

XXIV.

1.297

22.83

66.30

Isopropyl XXV.

1.3434

19.87

26 46

Isobutyl XXVI.

1.1598

17.68

38 46

XXVII.

1 1551

23.41

69 01

Isoaniyl XXVIII

1.4427

19.83

4870

XXIX.

1.4485

20.89

68.50

Benzyl XXX

1.0747

12.00

65.09

Phenol XXXI.

1.1227

9.78

24.90

An examination of Tables III. and IV. shows that the percent-
ages of nitrogen obtained with the ethylate are the only ones which
agree among themselves, the numbers with other alcoholates often
differing by about six per cent, in one case by nearly ten per cent.
Under these circumstances it is obviously unwise to attempt to
draw any definite inferences from these results; we therefore dis-
miss them with the general remark that the amount of nitrogen
removed seems to show a tendency to diminish as the molecular
weight of the alcohol increases.

The length of time during which the mixture of tribromtrinitro-
benzol and the alcoholate stood seemed to have but little influence
on the reaction, as is shown by Experiments V., XXIV., XXVII. ,

OP ARTS AND SCIENCES. 313

and XXIX., in which the mixture stood one or more days longer
than the eighteen hours used for the other experiments. In fact,
longer standing could not have any great effect in the case of the
ethylate, as in eighteen hours eighty to ninety per cent of the tri-
bromtrinitrobenzol had entered into the reactions. With the higher
alcoholates this was not the case, and it may he that the action had
not reached its end in eighteen hours, and that the variation ob-
served in the percentages was due to differences in the times of re-
action; but some experiments, in which the mixtures were allowed
to stand a longer time in order to test this point, gave unsatisfac-
tory results, apparently on account of the oxidation of the sodic
nitrite formed by the oxygen of the air.

PART III.

Action of Some Ethylate on Certain" Derivatives op TRI-
BROMTRINITROBENZOL CONTAINING AlKYLOXY RADICALS.

Action of Sodic Ethylate on the Triphenylether of Trinitro-
phloroglucine.

This work was undertaken in the hope that the triphenylether
of trinitrophloroglucine, C6(OC6H5)3(N02)3, might behave toward
sodic ethylate like tribromtrinitrobenzol, that is, lose one or more
nitro groups as sodic nitrite, which would be replaced by the ethoxy
group. This hope, however, has not been fulfilled, as instead of the
nitro groups the phenoxy radicals are removed by the sodic ethylate,
becoming replaced by ethoxy groups, while sodic phenylate is
formed. The experiments were carried on as follows. 2.5 gr. of
the triphenylether of trinitrophloroglucine* dissolved in benzol
were mixed with the sodic ethylate from 0.4 gr. of sodium, and the
bright red mixture allowed to stand two or more hours in the cold.
After this it was allowed to evaporate spontaneously, and the resi-
due warmed with water on the steam bath, when most of it dissolved.
The insoluble portion was purified by crystallization from alcohol

* In preparing this substance from tribromtrinitrobenzol again we have
found that a tolerable excess of sodic phenylate should be used in order to avoid
the formation of a compound containing bromine, — C(-(OC6H5)2Br(N(>,)3
probably. With such an excess, the reaction runs without heat, and is complete
in a few minutes. We have not observed the green color noticed by us last
year (these Proceedings, XXV. 188), which must therefore have been due to
some impurity.

314 PROCEEDINGS OF THE AMERICAN ACADEMY

until it showed the constant melting point 119-120°, which indi-
cated that it was trinitrophloroglucine triethylether, and this was
proved to be the case by the following analysis : —

0.2080 gr. of the substance gave 22.5 c.c of nitrogen at a tem-
perature of 21° and a pressure of 759.3 mm.

Calculated for
C6(OC,H5)3(N02)3. Found.*

Nitrogen 12.17 12.30

The aqueous filtrate which contained the other products of the
reaction beside the trinitrophloroglucine triethylether gave no test
for sodic nitrite, even with starch paste, potassic iodide, and sulphu-
ric acid. It was acidified with dilute sulphuric acid and extracted
with ether, which left an oily substance solidifying after some time,
and smelling strongly of phenol. To prove that this was phenol, it
was dissolved in a large quantity of water and bromine water added
to the solution, which gave a white precipitate melting constant
after c^stallization from dilute alcohol at 92°, the melting point
given by Post for tribromphenol; as however both Korner and Sin-
tenis give 95°, we thought it necessary to analyze the substance,
which was done with the following result: —

0.2803 gr. of the substance gave according to the method of Carius
0.4748 gr. of argentic bromide.

Calculated for
C6H2Br3OH. Found.

Bromine 72.51 72.07

There can be no doubt, therefore, that the substance is tribrom-
phenol, and that the action of the sodic ethylate upon trinitrophlo-
roglucine triphenylether takes place according to the following
reaction :

C6(OC6H5)3(N02)8 + 3NaOC2H5 = C6(OC2H5)3(N02)3 + 3NaOC6H6.

The bright red color observed in the solution was undoubtedly due
to some of the sodium salt of trinitrophloroglucine formed by the
action of the small amount of sodic hydrate, which it is almost im-
possible to exclude from sodic ethylate owing to the hygroscopic
nature of absolute alcohol.

* This analysis has also been given earlier in this paper, where the compo-
sition of the triethylether is first determined.

OP ARTS AND SCIENCES. 31")

This decomposition of the trinitrophloroglucine triphenylether
by sodic ethylate calls to mind the behavior of esters with another
alcohol and a small quantity of an alcoholate, as studied by Purdy *
and Peters,! especially as our ether approaches the esters on ac-
count of the marked acid properties of the trinitrophloroglucine.
Kossel and Kriiger $ have also found that sodic ethylate converts
salol into salicylic ester (or acid), and sodic phenylate, and that
glycerids are decomposed by sodic ethylate in a similar way, a
result which is confirmed by Obermuller.§

Action of Sodic Ethylate on Tribromnitroresorcine Diethylether.

Early in our work with the tribromnitroresorcine diethylether
melting at 101° we noticed that, although it was not acted on by a
cold solution of sodic ethylate in alcohol, it was attacked if heated
with such a solution, but our attempts to study this reaction were
baffled for a long time by the difficulty in removing from the crys-
talline product the large amount of tarry matter which was formed
at the same time, even constituting almost the whole of the mass,
if the heat was not applied cautiously. After many experiments
we succeeded in obtaining a satisfactory result by proceeding as
follows. 13 gr. of tribromnitroresorcine diethylether were cov-
ered with absolute alcohol, and an alcoholic solution of sodic
ethylate added. The flask containing the mixture was, after fitting
it to a return condenser, immersed in a beaker of cold water, which
was heated slowly. As the temperature rose the substance went
into solution with a pale reddish color, and in a few minutes after
that there was a sudden change, the solution becoming almost black,
although the reaction was not at all violent. At this point the
heating must be stopped to avoid the formation of a large quantity
of the tarry impurity. The contents of the flask, which had a pe-
culiar aromatic odor not belonging to the compound we have isolated,
was allowed to evaporate to dryness spontaneously, and the residue
washed several times with cold water, which was found to contain
sodic bromide. The water left undissolved a most unpromising
tarry mass with almost no sign of crystalline form, but by extracting
it with hot ligroine a crystalline substance was obtained, which was
purified by repeated crystallization from hot alcohol with the aid of

* Ber. d. ch. Ges., XX. 1554. \ Zeitschr. Physiol Chem., XV. 321.

t Ann. Chem , CCLVII. 353. § Ibid , XVI. 152.

316 PROCEEDINGS OF THE AMERICAN ACADEMY

bone-black until it melted constant at 115°, when it was dried at
100° and analyzed with the following results : —

I. 0.1897 gr. of the substance gave on combustion 0.2874 gr.
of carbonic dioxide and 0.0782 gr. of water.
II. 0.1519 gr. of the substance gave according to the method of
Carius 0.0985 gr. of argentic bromide.

Found.

II.

Carbon

Calculated for
C6H2BrN02(OCjH5),.

41.38

i.
41.31

Hydrogen
Bromine

4.14

27.58

4.58

27.60

The substance has therefore been formed from the tribromnitro-
resorcine diethylether by the replacement of two atoms of bromine
by two of hydrogen, a reaction which is similar in principle to the
replacement of the bromine by hydrogen in bromdinitroresorcine
diethylether, when treated with a boiling solution of sodic ethylate
in alcohol, and to the similar replacements of bromine by hj'drogen
in the formation of bromdinitrophenylmalonic ester and related sub-
stances from tribromdinitrobenzol and tribromtrinitrobenzol.

Properties of Bromnitroresorclne Diethylether,
C6H2BrN02(OC2H5)2.

The substance crystallizes from hot alcohol in long radiating
silky white needles, which melt at 115°, and are soluble in cold
alcohol, more freely in hot; freely soluble in cold methyl alcohol;
very freely in benzol, chloroform, acetone, glacial acetic acid, or
carbonic disulphide; slightly soluble in cold ligroine, much more
soluble in hot; essentially insoluble in water. Neither hydrochlo-
ric, nitric, nor sulphuric acid seems to have any action on it, and
the same is the case with a solution of sodic hydrate.

OF ARTS AND SCIENCES. 317

XXII.

CONTRIBUTIONS FROM THE CHEMICAL LABORATORY
OF HARVARD COLLEGE.

ON THE ACTTOX OF WATER UPON TRIBROMTRLNl-
TROBENZOL AXD TRIBROMDIXITROBEXZOL.*

By C. Loring Jackson and W. H. Warren.

Presented June 15, 1892.

In an article f recently published, C. A. Lobry de Bruyn de-
scribes the action of an aqueous solution of sodic carbonate upon
the unsymmetrical trinitrobenzol (1, 2, 4) which produces the
dinitrophenol (OH, 1, 2, 4) by the replacement of a nitro group by
hydroxyl. After we had shown in an earlier paper J that the nitro
groups can be removed from tribromtrinitrobenzol by sodic alcohol-
ates, M. Lobry de Bruyn suggested to us in the most courteous way
that it would be interesting to see whether an aqueous solution of
sodic carbonate would not have a similar effect on this substance,
which seemed not improbable after his work already cited. The
following paper contains an account of the work we undertook in
accordance with this suggestion, the results of which can be briefly
summarized as follows. Symmetrical tribromtrinitrobenzol (melt-
ing point 285°) is converted by boiling with sodic carbonate and
water into a mixture of the sodium salts of trinitrophloroglucine
and a tribromdinitrophenol, C6Br3(X02)2OH, melting at 194°,
which, so far as we can find, has not been described as yet. Tri-
bromdinitrobenzol (melting point 192°, made from symmetrical tri-
brombenzol) gave under the same conditions a dibromdinitrophenol
which melts at 147-148°, a melting point almost identical with
that of the only other dibromdinitrophenol known (146°-146°.5),

* The work described in this paper formed part of a thesis presented to the
Faculty of Arts and Sciences of Harvard University for the degree of Doctor of
Philosophy, by W. H. Warren.

t Rec. Trav. Chem., IX. 185.

t These Proceedings, XXV. 164.

818 PKOCEEDINGS OF THE AMERICAN ACADEMY

recently made by Garzino * by the action of nitric acid on the pro-
pionic ester of metabromphenol. This coincidence is, however,
purely accidental, as in Garzino's phenol the bromine atoms stand
in the ortho and para, in ours in the meta positions, to the hy-
droxyl. As was to be expected, the two phenols gave different
salts, the potassium salt made by Garzino, containing one half of
a molecule of water, while ours is anhydrous, his barium salt con-
taining three, ours two molecules of water. Mixed with the
dibromdinitrophenol is an oily phenol, which we have not suc-
ceeded in purifying in spite of many attempts.

The two substances, therefore, act with water and sodic carbonate
in the same general manner as with sodic ethylate, the trinitro
compound in both cases showing two parallel reactions, in one of
which nitro groups, in the other bromine atoms, are removed, while
the dinitro compound in both cases loses part of its bromine. It is
to be observed, however, that while the alcoholate removes two
nitro groups from the trinitro and two bromine atoms from the
dinitro compound, water in each of these cases removes only one;
although, like the alcoholates, it removes all three of the bromine
atoms from the tribromtrinitrobenzol.

The constitution of the new tribromdinitrophenol can be onl}r
C6OHBi\N"02BrN02Br, as the substance from which it is derived is
symmetrical. The dibromdinitrophenol, on the other hand, can be
either C6OHN02BrN02BrH or C6OHN02BrHBrN02, and we have
no experimental data for determining which of these two formulas
is correct.

Action of Water and Sodic Carbonate on Tribromtrinitrobenzol.

As this action takes place very slowly it is better to carry it on
as follows. Four or more flasks provided with return condensers
were charged each with about 1 gr. of tribromtrinitrobenzol and a
moderate quantity of a dilute solution of sodic carbonate, and al-
lowed to boil for twelve or more hours. After a short time the
solution turned yellow, and at the end of the boiling had become
deep red. The unaltered tribromtrinitrobenzol was filtered out, and
boiled again with a fresh solution of sodic carbonate. The deep red
filtrate showed the presence of sodic bromide and sodic nitrite when
the proper tests were applied. When acidified with dilute sulphu-

* Att. R. Ace. Sc. Torino, XXV. 263. Ber. d. ch. Ges., 1892, R. 119.

OF ARTS AND SCIENCES. 319

ric acid it turned from red to yellow, and a white precipitate was
thrown down, to which we first turned our attention.

The white product of the reaction, which is insoluhle in water,
was purified by dissolving it in amnionic hydrate, precipitating the
barium salt from this solution by means of baric chloride, and treat-
ing the precipitate with alcohol, in which the barium salt of this
substance is soluble. The filtered alcoholic solution was evapo-
rated to dryness, the residue recrystallized several times from hot
water, and then converted back into the free phenol by treatment
with dilute hydrochloric acid. The free phenol was next dissolved
in as little hot alcohol as possible, diluted with water till a pre-
cipitate began to form, which was then redissolved by the addition
of a drop or two of alcohol, when upon cooling the substance sepa-
rated in good crystals. This rather long method of purification
can be replaced by simple crystallization of the free phenol from
alcohol and water in the way just described, but, if an absolutely
pure product is needed, the whole method described above should
be used. After it showed the constant melting point 194°, it was
dried at 100° and analyzed with the following results: —

I. 0.1951 gr. of the substance gave 12 c.c. of nitrogen at a tem-
perature of 23° and a pressure of 768.1 mm.
II. 0.2089 gr. of the substance gave according to the method of
Carius 0.2787 gr. of argentic bromide.

Nitrogen

Calculated for
C6Br.j(N0,)20H.

6.65

Found.
I. II.

7.00

Bromine

57.01

56/

These analyses show that the substance is a tribromdinitrophenol,
and as it must have been formed from the tribromtrinitrobenzol by
replacing one of the nitro groups by h3'droxyl its constitution must
be represented by the formula CcOHBrlSrC^BriSrOoBr. It is, so far
as we are aware, the first tribromdinitrophenol which has been
made.

To confirm the results of the preceding analyses the sodium salt
was made by treating an excess of the phenol with pure sodic
hydrate, filtering, and crystallizing from hot water, when it sep-
arated in long filiform yellow needles.

0.3076 gr. of this sodium salt gave 0.0504 gr. of sodic sulphate.

Sodium

Calculated for

C6Br?(NO,).,0Xa.

Found

5.19

5.31

320 PROCEEDINGS OP THE AMERICAN ACADEMY

The sodium salt is soluble in ethyl or methyl alcohol even in
the cold, and crystallizes from its alcoholic solution in long, flat,
pointed needles.

Properties of Tribromdinitrophenol. — This substance crystal-
lizes from dilute alcohol in square-ended needles usually grouped
in arborescent or fan-shaped clusters looking like certain seaweeds;
its color is white with a very faint shade of yellow. It melts at
194°, and is freely soluble in cold ethyl or methyl alcohol, or in
ether, acetone, or glacial acetic acid ; somewhat less soluble in
benzol or chloroform, although still freely soluble in these liquids;
soluble in carbonic disulphide; slightly in ligroine; very slightly
in cold water, somewhat more soluble in hot. Dilute alcohol is
the best solvent for obtaining crystals. Its alcoholic solution is
distinctly yellow. The three strong acids have no apparent action
on it. With alkalies it forms colored salts. A solution of the
sodium salt gave precipitates consisting of yellow needles with
salts of zinc, nickel, manganese, cobalt, chromium, cadmium, or
lead. Cupric salts gave light green needles. In order to char-
acterize the substance still further, its barium salt was prepared
and analyzed.

Baric Tribromdinitrophenylate, [C6Br3(N02)20]2Ba. — This sub-
stance was made by adding baric chloride to a concentrated solu-
tion of the ammonium or sodium salt, collecting the precipitate,
and recrystallizing it several times from hot water. The salt con-
tained no water of crystallization.

I. 0.6621 gr. of the salt gave 0.1545 gr. of baric sulphate.
II. 0.5066 gr. of the salt gave 0.1182 gr. of baric sulphate.

Calculated for

Found.

[CGBr3(N02)20]2Ba.

I II.

14.03

13.72 13.72

Barium

The baric tribromdinitrophenylate crystallizes from hot water in
long yellow needles arranged in radiating circular groups. It is
slightly soluble in cold water, more soluble in hot; freely in cold
ethyl or methyl alcohol.

After the tribromdinitrophenol obtained by the acidification of
the products of the reaction of water and sodic carbonate on tri-
brominitrobenzol had been filtered out, the filtrate was extracted
with ether to obtain the organic substance, whose presence was in-
dicated by its yellow color. The extract thus obtained melted over
190°, and contained bromine, indicating the probable presence of

OF ARTS AND SCIENCES. 321

some tribromdinitrophenol. Upon boiling it with an aqueous solu-
tion of potassic carbonate, and allowing the solution to cool, small
orange needles were obtained, which on acidification yielded the
tribromdinitrophenol reoognized by its crystalline form and melt-
ing point. The highly colored filtrate from these crystals was now
treated with dilute sulphuric acid, extracted with ether, and the
extract crystallized from water by slow evaporation, when the char-
acteristic hexagonal prisms of trinitrophloroglucine were obtained.
As they showed a somewhat low melting point, 163-164°, instead
of 167°, (see the preceding paper,) the original substance and its
barium salt were analyzed with the following results : —

0.2130 gr. of the substance gave 30.3 c.c. of nitrogen at a tem-
perature of 19°. 5 and a pressure of 776.1 mm.

Calculated for

C6(OH)3(N02)3 Found.

Nitrogen 16.09 16.67

0.7080 gr. of the barium salt gave 0.5409 gr. of baric sulphate.

Calculated for
[C603(NT0„)3],Ba3. Found.

Barium 44.33 44.91

The barium salt contained no water of crystallization. These
analyses leave no doubt that the substance is trinitrophloroglucine,
and the behavior of tribromtrinitrobenzol with water is therefore
represented by the following reactions : —

CGBr3(N02)3 + 3 H20 = C6(OH)3(N02)3 + 3 HBr.
C6Br3(X02)3 + H20 = C6Br3(N02)2OH + HX02.

The action of sodic hydrate and water upon tribromtrinitrobenzol
was similar to that of sodic carbonate and water, the products being
trinitrophloroglucine and tribromdinitrophenol. The action in this
case takes place somewhat more quickly than with the carbonate,
but we preferred to use sodic carbonate in order to avoid the ac-
tion of the boiling hydrate upon the glass of the flask. In the cold,
sodic hydrate seemed to have no action on tribromtrinitrobenzol,
which surprised us because Lobry de Bruyn * has found that it
acts in the cold on the unsymmetrical trinitrobenzol.

* Rec. Trav. Chem., IX. 193.
vol. xxvn. (n. s. xix.) 21

322 PROCEEDINGS OF THE AMERICAN ACADEMY

Action of Tribromdinitrobenzol with Water and Sodic

Carbonate.

Tribromdinitrobenzol (melting point 192°, made from symmet-
rical tribrombenzol) was boiled with an aqueous solution of sodic
carbonate in the way just described for the trinitro compound.
The action in this case was so slow that it was found better to con-
tinue the boiling for. at least twenty-four hours before filtering.
As in the preceding case, the color of the solution gradually be-
came j'ellow, and later changed to red. After filtering out the
unaltered tribromdinitrobenzol, the red filtrate, which contained
sodic bromide and sodic nitrite, was acidified with dilute sulphuric
acid, which turned it light yellow, and produced a cloudy precipi-
tate, which after a long time collected on the bottom in the form
of oil-drops. These were removed, the clear liquid extracted with
ether, and the extract, which was small in amount and oily, added
to the oil which had separated. This was then dissolved in am-
nionic hydrate and treated with baric chloride, when a precipitate
was formed in a dark red solution.

The insoluble barium salt was decomposed with hydrochloric
acid, and the phenol thus set free crj'stallized from dilute alcohol
until it showed the constant melting point 147-148°, when it was
dried at 100°, and analyzed with the following results: —

I. 0.1626 gr. of the substance gave by the method of Carius
0.1804 gr. of argentic bromide.
II. 0.2053 gr. of the substance gave 15.7 c.c. of nitrogen at a
temperature of 26° and a pressure of 759.9 mm.

Calculated for

Found.

C6HBr,0H(N02)2.

I. II

romine

46.78

47.22

itrogen

8.19

8./

These results prove that the substance is a dibromdinitrophenol
formed by the replacement of one atom of bromine by one of hy-
droxyl, and as it is made from a s}rmmetrical tribrom compound it
must be isomeric with the one melting at 146°-146°.5 made by
Garzino from metadibromphenol.

Properties of Dibromdinitrophenol. — This substance c^stallizes
from a hot alcoholic solution diluted with water until the substance
begins to precipitate in thick yellow needles with square ends,' ar

OF ARTS AND SCIENCES. 323

ranged in radiating groups, although occasionally forms with two
comb edges were observed. If crystallized from alcohol alone, in
addition to the thick needles or prisms, other rather broad prismatic
forms are observed, which have a notch in each end so that they
resemble reels, or, wdien this formation is carried farther so that the
notch has a flat bottom, crystals resembling spools are produced.
Both these latter forms are very characteristic. It melts at 147-
148° ; and is very freely soluble in ethyl or methyl alcohol even
in the cold, in ether, acetone, or glacial acetic acid; freely soluble
in benzol or chloroform; soluble in carbonic disulphide; nearly
insoluble in ligroine; water dissolves it to a certain extent when
cold, still more, although not freely, when hot. The three strong
acids have no apparent action on it. Alkalies form yellow salts
with it.

Potassic Dibromdinitrophenylate, C6HBr2OK(X02)2- — This salt
was prepared by heating the free phenol with an aqueous solution
of potassic carbonate, and was purified by crystallization from
hot water. The salt was found to be free from water of crys-
tallization. 0.1806 gr. of the air-dried salt lost only 0.0005 gr. at
120°. Garzino found one half of one molecule of water in his
potassic dibromdinitrophenylate. The salt dried at 120° gave the
following result on analysis : —

0.1664 gr. of the salt gave 0.0390 gr. of potassic sulphate.

Calculated for C6HBr2OK(NO,), Found.

Potassium 10.29 10.52

The salt crystallizes from hot water in arborescent clusters of
orange-yellow needles, which are somewhat soluble in alcohol, but
not freely even when it is hot.

Baric Dibromdinitrophenylate, [C6HBr20(X02)2]2Ba2H20. — The
salt was made by boiling the phenol with water and baric carbonate,
and purified by crystallization from boiling water, when it was
analyzed with the following results: —

I. 0.2834 gr. of the salt dried in the air lost 0.0116 gr. at 120°.
II. 0.2834 gr. of the air-dried salt lost 0.0135 gr. at 120°.
III. 0.2831 gr. of the air-dried salt lost 0.0121 gr. at 120°.

Wat

or

Calculated for

Found.

[C,,nBr20(N02)2]2Ba2H20.

i

II

III.

4.21

4.09

4.76

4.27

C24 PROCEEDINGS OP THE AMERICAN ACADEMY.

Three molecules of water of crystallization, the amount found by
Garzino in his barium salt, would give 6.19 per cent of water.

IV. 0.3923 gr. of the salt dried at 120° gave 0.1112 gr. of baric
sulphate.
V. 0.2668 gr. of the salt dried at 120° gave 0.0754 gr. of baric
sulphate.

Calculated for Found.

[CBHBr,0(N02)2]aBa. IV. V.

Barium 16.73 16.66 16.62

The salt is yellow while it contains its water of crystallization,
but turns orange as it loses it, and this change takes place in a
desiccator over sulphuric acid, as under these circumstances it loses
all but an insignificant fraction of the water which it contains.
The dried salt absorbs water very eagerly from the air, turning from
orange to yellow again. It crystallizes from boiling water in clus-
ters of radiating needles, and is soluble in alcohol.

The dark red filtrate from the precipitate of the barium salt of
dibromdinitrophenol gave upon acidification an oily precipitate,
which has resisted all our efforts to bring it into a state fit for
analysis; it is probable that this could be done by often repeated
fractional precipitation, but we do not think the identification of
the substance of sufficient importance to justify the large expendi-
ture of time and work necessary to provide material enough for this
purpose. Several analyses, which we made to determine the purity
of our preparations, seemed to point to the presence of a substance
having the composition C6HBr2N02(OH)2, but, as at the same time
they proved that our products were decidedly impure, no weight
should be given to this indication, although the formation of some
such substance is to be expected from the appearance of sodic
nitrite among the products of the reaction.

Sodic hydrate acts upon tribromdinitrobenzol in the same way
that sodic carbonate does, but somewhat more rapidly. It has ap-
parently no action in the cold.

PROCEEDINGS.

Eight hundred and forty-third Meeting.

May 26, 1891. — Annual Meeting.

The President in the chair.

The death of D. Ceeilio Pujazon, Director of the San Fer-
nando Observatory, was announced ; also, the death of Carl
Wilhelm von Naegeli, of Munich, and of Carl Johann Maxi-
mowicz, of St. Petersburg, Foreign Honorary Members.

The Corresponding Secretary read the annual report of
the Council.

The Treasurer and the Librarian presented their annual
reports.

The following report was presented : —

Report of the Rumford Committee.

The Committee have held various meetings during the year with
reference to the selection of a suitable candidate for the Rumford
Medals. They respectfully submit that, in their opinion, the work of
Professor E. C. Pickering on the photometry of the stars, and his
work upon Stellar Spectra, fully justify the award to him of the Rum-
ford Medals. By his invention of the meridian photometer he has
succeeded in bringing order out of the chaos of photometric measure-
ments hitherto made, by referring the photometric measures of all
other stars to that of the Pole-star, and thus furnishing an estimate
of the change of brightness of the stars with reference to the standard
Pole-star. Estimates of the brightness of this star are also made, so
that the photometry of the stars has been put upon a basis never
before attained.

In his work upon the Draper memorial, Professor Pickering, adopt-
ing the method of Frauenhofer, and greatly enlarging the prisms and
objectives employed by the latter, has succeeded in obtaining Stellar

326 PROCEEDINGS OF THE AMERICAN ACADEMY

Spectra which are comparable in size to the spectrum of the Sun as it
was known to Frauenhofer. The method of the latter consisted in
placing a prism of small refracting angle directly in front of the ob-
jective of the telescope, and in dispensing with the collimator. A
cylindrical lens was employed to spread out the more or less linear
spectra thus obtained. Frauenhofer's objective was about four inches
in diameter, and the prism was a small one, suitable for this aperture.
Professor Pickering employed a lens of eight inches in aperture, and
a prism eight inches square, with a refracting angle of thirteen de-
grees. In some cases, three and four prisms were employed. The
spectra were enlarged by means of a cylindrical lens, and also by
giving the negative a motion in the direction of the lines upon the
negative.

Professor Pickering has also employed spectrum analysis to the
determination of the motions of the components of variable stars.
He has discovered a large number of nebulae and stars with singular
spectra. A catalogue of stars with various types of spectra is now
under way. The first volume of this catalogue has already beeu pub-
lished. This work on stellar spectra is greatly in advance of any-
thing else on this subject which lias been done, and is worthy, in the
opinion of the committee, of the award of the Rumford Medals.

For the Committee,

J. Lovering, Chairman.

This report was accepted by the Academy, and it was
Voted, That the Rumford Medal be awarded to Professor
Edward C. Pickering.

On the motion of Professor Trowbridge, it was
Voted, To appropriate from the income of the Rumford
Fund one hundred dollars ($100) to Professor E. H. Hall
for an investigation of the conduction of heat in the walls of
the cylinder of the steam-engine, and two hundred and fifty
dollars ($250) to Professor B. O. Peirce for an investigation
of the conduction of heat in the interior of solid bodies.

The following appropriations from the general fund were
voted : —

For publications $1,500

For the library 1,200

For the expenses of meetings . . . 200

OF ARTS AND SCIENCES. 327

On the motion of the Treasurer, it was

Voted, That the annual assessment for the ensuing year be
five dollars.

The following gentlemen were elected members of the
Academy : —

Henry Taber, of Worcester, to be a Resident Fellow in
Class I., Section 1.

Henry Marion Howe, of Boston, to be a Resident Fellow
in Class I., Section 3.

Louis Cabot, of Brookline, to be a Resident Fellow in
Class II., Section 3.

Josiah Royce, of Cambridge, to be a Resident Fellow in
Class III., Section 1.

Abner Cheney Goodell, Jr., of Salem, to be a Resident
Fellow in Class III., Section 3.

Thomas Corwin Mendenhall, of Washington, to be an As-
sociate Fellow in Class I., Section 2, in place of the late John
H. C. Coffin.

George Park Fisher, of New Haven, to be an Associate
Fellow in Class III., Section 3, in place of the late George
Bancroft.

The annual election resulted in the choice of the following
officers : —

Joseph Lovering, President.
Andrew P. Peabody, Vice-President.
Josiah P. Cooke, Corresponding Secretary.
William Watson, Recording Secretary.
Eliot C. Clarke, Treasurer.
Henry W. Haynes*, Librarian.

Council.

Arthur Searle,

William E. Story, \ of Class I.

Charles R. Cross,

Samuel H. Scudder,

David W. Cheever, \ of Class II.

Sereno Watson,

328 PROCEEDINGS OP THE AMERICAN ACADEMY

Edward J. Lowell, \

Martin Brimmer, > of Class III,

Lucien Carr, )

Rumford Committee.
WOLCOTT GlBBS, JOSEPH LOVERING,

John Trowbridge, George B Clark,

Josiah P. Cooke, Erasmus D. Leavitt,

Benjamin O. Peirce.

Member of the Committee of Finance.
Augustus Lowell.

The President made appointments as follows : —

Committee of Publication.

Josiah P. Cooke, William G. Farlow,

John C. Ropes.

Committee on the Library.

Henry P. Bowditch, Amos E. Dolbear,
Edward J. Lowell.

Auditing Committee.
Henry G. Denny, Augustus Lowell.

The following papers were presented by title : —

On a Kephir-like Yeast found in the United States. By
Charles L. Mix.

On the Matrical Equation <f>fl = f2<f>. By Henry Taber.

On the Movement of Electricity in Iron. By John Trow-
bridge and W. C. Sabine.

Eight hundred and forty-fourth Meeting.

June 10, 1891. — Monthly Meeting.

The President in the chair.

A biographical notice of Henry Jacob Bigelow, by Dr.
Oliver W. Holmes, was read.

OF ARTS AND SCIENCES. 329

The following papers were presented by title : —

Notes on Fungi. By William G. Farlow.

Concerning the Life-History of Saccorhiza dermatodea (De
la Pyl.) J. Ag. By William A. Setchell.

A Revision of the Atomic Weight of Copper. Fourth
Paper. By Theodore W. Richards.

On some Considerations regarding Helmholtz's Theory of
Consonance. By Charles R. Cross and Harry M. Goodwin.

On the Minimum Number of Vibrations necessary to deter-
mine Pitch. By Charles R. Cross and Margaret E. Maltby.

Eight hundred and forty-fifth Meeting.

October 14, 1891. — Stated Meeting.

The President in the chair.

The following letters were read by the Corresponding
Secretary : from Louis Cabot, accepting Fellowship in the
Academy ; from the Tacoma Academy of Science, announcing
its formation, and asking for the publications of the American
Academy ; from the Royal Academy of Sciences of Lisbon,
announcing the death of its Secretary, Jose* Maria Latino
Coelho ; from George Walter Hael, claiming that the clefts
found upon the earth and the moon are due to the action of
meteors; from the friends of Wilhelm Weber, announcing
his death ; from Eduard Marchal, announcing his election
as Permanent Secretary of the Royal Academy of Belgium ;
from J. Veniezra, announcing his appointment as Director of
the Marine Observatory of San Fernando; from the Royal
Society of New South Wales, enclosing a programme of sub-
jects for medals and money prizes to be obtained by compe-
tition ; and from W. K. Warren, executor of the estate of
Cyrus M. Warren, Fellow of the Academy, announcing a
bequest to the Academy.

On motion of the Treasurer, the following vote was
passed.

Whereas, The will of our late honored Associate, Cyrus M.
Warren, contains the following provisions : —

330 PROCEEDINGS OP THE AMERICAN ACADEMY

" VII. I give and bequeath to the American Academy of Arts and
Sciences of Boston oue hundred shares of the capital stock of the
Warren-Scharf Asphalt Paving Company, the proceeds, dividends, and
income thereof to be applied by the said Academy, its trustees or
directors, in their discretion, for the encouragement and advancement
of research in the science or field of chemistry.

" VIII. I give and bequeath to said American Academy of Arts
and Sciences fifty shares of the capital stock of the said Warren-
Scharf Asphalt Paving Company, the proceeds thereof to be applied
to or towards a building fund, for the purpose of erecting a building
for the use of the library of said Academy, and for holding the meet-
ings of said Academy ; the same to be used in erecting such a struc-
ture when, in the opinion of the directors or trustees of said corpo-
ration, a sum sufficient shall be realized to justify such erection."

Voted, That the American Academy of Arts and Sciences
accepts said bequests, and directs its Treasurer to keep the
funds arising from them distinct, so that they may be applied
in accordance with the conditions recited in the will.

The following gentlemen were elected members of the
Academy : —

Warren Upham, of Somerville, to be a Resident Fellow in
Class II., Section 1.

William Brewster, of Cambridge, to be a Resident Fellow
in Class II., Section 3.

Edward Gardiner Gardiner, of Boston, to be a Resident
Fellow in Class II., Section 3.

Samuel Jason Mixter, of Boston, to be a Resident Fellow
in Class II., Section 4.

On motion of Dr. Williams, it was

Voted, To amend Standing Vote 10 by substituting " may "
for "shall."

As amended, the standing vote reads as follows: —

" 10. A meeting for receiving and discussing scientific communi-
cations may be held on the second Wednesday of each month not
appointed for stated meetings, excepting July, August, and Sep-
tember."

OF ARTS AND SCIENCES. 331

Eight hundred and forty-sixth Meeting.

January 13, 1892. — Stated Meeting.

The Academy met at the house of the Hon. Martin
Brimmer.

The Vice-President in the chair.

On the motion of the Recording Secretary, it was

Voted, To meet on adjournment on the second Wednes-
day in February next.

The chairman, in a brief address, announced that the Rum-
ford Premium had been awarded to Professor Edward C.
Pickering for his work on the photometry of the stars and
upon stellar spectra.

Professor Pickering, in response, gave an account of the
photographic work under his direction at the various stations
in North and South America.

Dr. William Everett announced the death, on the 19th of
December, 1891, of Sir George Biddell Airy, late Astronomer
Royal, at Greenwich, elected a Foreign Honorary Member on
the 25th of January, 1832, and since the death of Robert
Treat Paine, in 1885, the senior member of the Academy.

Dr. William W. Jacques presented a paper entitled,
" What Electricity is." This paper was illustrated by a new
piece of apparatus invented by Dr. Jacques.

In the discussion which followed, Professor Cross, Judge
Holmes, and Major Livermore participated.

Eight hundred and forty-seventh Meeting.

February 10, 1892. — Adjourned Stated Meeting.

The Vice-President in the chair.

The death on the 18th of January of Joseph Lovering,
President of the Academy, was announced, and the meeting
was devoted to a commemoration of his life and services.

The Vice-President, Rev. Andrew P. Peabody, opened the
proceedings with the following words : —

832 PROCEEDINGS OP THE AMERICAN ACADEMY

We are convened this evening to express our sorrow for the death
of our late President, and to offer our tribute to his memory. While
it belongs to me officially to lead in the proceedings of the meeting,
there is a certain fitness in my doing so, as my knowledge of Mr.
Lovering antedated that of any one else here present. Most of you
were his pupils ; he was my pupil. In his Senior year in college his
class recited in Astronomy to me. My only remembrance of him in
the class-room is that he was one of the three or four on whom I
relied to do credit to the class and' their teacher in the oral examina-
tion at the end of the term. But he was brought into closer relation
with me in another department. With three or four of his classmates
he studied Hebrew with me for that entire year, and for that purpose
spent three hours a week in my room. I then learned to admire the
diligence, promptness, and accuracy which have marked his life-work
ever since. He became, so far as was possible in a single year, a pro-
ficient in that language, which many who ought to be conversant with
it find so hard to learn and so easy to forget.

Immediately after graduating he entered the Divinity School, and
had nearly completed his preparation for the ministry when, in con-
sequence of Professor Farrar's illness, he was requested to continue
and complete a course of lectures in the department of Physics.
Professor Farrar became a chronic invalid, and the place which Mr.
Lovering first filled in an emergency he held, as Tutor and Professor,
for fifty-three years. It was no small thing to succeed Professor
Farrar. Those who heard his lectures, of whom few survive, were
wont to speak of him as the most eloquent of men. Yet from the very
first, both in Physics and in Astronomy, Mr. Lovering won a reputation
that gave him a foremost rank as a scientific lecturer, which remained
his when the grandchildren of his early classes sat under the wordfall
still fresh and bright, because both old and ever new.

I speak here not only from abundant testimony, but from my own
hearing. While the Lyceum was still an educational institution and
enlisted the best men in its service, I had the pleasure of listening to
several of his astronomical lectures, and at the same time of receiving
him as my guest. I then could recognize at once the thoroughness
of his scientific scholarship, his clearness of apprehension, his unsur-
passed teaching power, and his gifts of style and manner, which
could not but secure for him a marvellously strong hold on an
intelligent audience.

Since my return to Cambridge I have been intimately associated
with him, and these years have given me constant, and, were there

OF ARTS AND SCIENCES. 333

room for growth, growing experience of traits of mind, heart, and
character which have won my profound respect and sincere affection.

In the sixty years for which I have known him, there has been
nothing in deed or word to break the record of a life pure, true, faith-
ful, and kind. Rigidly conscientious in the least things as in the
greatest, he has shown the worth and power of the religion whose
worship and ordinances he has held in constant and sacred observance.

So young seemed he for his years, we looked not that he should be
taken from us thus early. With bodily strength but slightly impaired,
he retained his clearness, vigor, and activity of mind to the last. We
are thankful that he passed away while we can feel his loss and
mourn his departure, — that he was spared the prolonged decline and
infirmity which we who are growing old most of all dread and dep-
recate. His life was beautifully rounded ; its work done, and well
done; and he was happy in the timeliness of his death no less than in
the gratitude and honor which grew with his years, crowned his old
age, and insure for him a precious and blessed memory.

With the approval of the Council, I offer for the Academy the
following resolutions: —

o

Resolved, That, in the death of our late President, the Academy has
lost a member whose reputation and whose many years of loyal service
have contributed lai-gely to its honor and prosperity, and a presiding
officer whose assiduity, courtesy, and kindness have won for him from all
his associates the most cordial and grateful regard.

Resolved, That we hold in precious remembrance his high scientific
attainments, his eminent ability and success as a teacher, his place among
the foremost in the reverence and love of the graduates of Harvard Uni-
versity, his pure and elevated character, and the worth of his example and
influence as a Christian gentleman and scholar to the successive classes of
students who, for more than half a century, passed under his instruction
and discipline.

Resolved, That a copy of these resolutions be sent to his family, with
the expression of our sincere sympathy with them in their bereavement.

The resolutions offered by the Vice-President were sec-
onded by President Eliot of Harvard University: —

Professor Lovering's life seems to me to be better characterized by
the word fidelity than by any other. He was just as faithful in the
least things as in the greatest. Whatever work he undertook, he did
thoroughly and steadily, although it might be uninteresting, mechan-
ical, or really unsuitable for one of his station and powers. He heard

334 PROCEEDINGS OP THE AMERICAN ACADEMY

recitations in Lardner's Natural Philosophy for many years of his
life, and for a part of the time he heard each lesson three times over, —
the class in Physics being divided into three sections. The book was
very elementary, and far from interesting, and the class was boyish in
attainments and in spirit ; but year after year he performed that
humble function with an absolute fidelity. For many years he gave
illustrated lectures on all the main subjects in Physics, — generally
two lectures a week throughout the academic year ; and he himself
made all the preparation for the experiments, with no assistance
except that of the bell-ringer, who came in to help him move heavy
pieces of apparatus or to work the air-pump. With perfect patience
he performed weekly for years, without any assistant, this great
amount of manual labor in connection with his lectures ; and, as his
lectures were repeated year after year during more than forty years,
the weariness of repetition was added to the physical fatigue.

For twelve years, from 1857 to 1869, he was Regent of the College.
That officer kept the records of absences and of the marks received by
the students at their recitations. With his own hand Professor Lov-
ering entered the absences and the marks in the record books, kept
watch on the absences of every student in College, considered excuses,
and reported delinquents to the Faculty week by week. The Regent
exercised discretion and needed good judgment ; but far the greater
part of his time was devoted to accurate, patient, clerical labor. He
was in his office three days of the week for two hours each day, and
his compensation was five hundred dollars a year. I mention these
details because they perfectly illustrate a quality in Professor Lover-
ing which the men of a younger generation may well imitate, — a
capacity for assiduous routine labor. Every great scholarly achieve-
ment is accomplished by just such faithful industry. An inspiration is
a momentary flash ; a high purpose has an instant of formation ; but
inspiration and purpose have to be wrought out through years of
unremitting labor.

I have always admired in Professor Lovering the mixture of con-
servatism with openness of mind. His natural conservatism was
modified by a true scientific candor. Change for its own sake he
never desired ; but he could be convinced by experience that a given
change was an improvement. He held to the opinions and practices
which he had adopted before he was forty years old ; but his mind
was also open to new projects. When the rapid expansion of Har-
vard University began in 1866, just after the close of the Civil War,
Professor Lovering was already fifty-three years old and bad been

OF ARTS AND SCIENCES. 335

thirty years in the College service. When I was elected President he
was fifty -six, — a time of life at which many men become impatient of
changes which seriously affect their own habits of work. Yet Pro-
fessor Lovering welcomed the project of moving the entire physical
establishment from its narrow quarters in University Hall to larger
rooms in Harvard Hall. He personally arranged the lower floor of
Harvard Hall to receive the Department of Physics, and was highly
content with the new accommodations of the department when the
transfer was completed, in 1870. But the department grew apace,
and the great gift of Mr. T. Jefferson Coolidge for the construction of
a new physical laboratory made it possible to provide the department
with larger quarters still, and opened the way to a great increase both
of the teaching and of the investigation which it carried on. At the
age of seventy-one Professor Lovering entered heartily into this
large undertaking, brought to it a flexible and fertile mind, moved
again from Harvard Hall to the Jefferson Physical Laboratory, and
was glad to be appointed the first Director of that ample establish-
ment.

He had been all his life an advocate of a single prescribed curriculum
for Harvard College, whereby every student should pursue the same
subjects ; but after he was established as Director of the Jefferson
Physical Laboratory, and had at his disposition an admirable lecture-
room and a much enlarged cabinet of apparatus, I asked him one day
if he would give some lectures to the Freshmen on general physics ;
for I wanted the Freshmen to have the advantage of his singular
clearness of exposition. He asked if the Freshmen were not required
to attend those lectures, — a question which then could only be an-
swered in the affirmative. Whereupon he refused to give the lectures,
saying that he would never again lecture in a required course, or to
an audience whose attendance was required.

As I look back upon his life, it seems to me that it was to an ex-
traordinary degree independent and self-contained. While entirely
devoted to Harvard University as an institution, and inclined by tem-
perament to support the constituted authorities of the University, he
was nevertheless peculiarly independent in his own professorship, and
had been ever since he was first elected to his chair, at the age of
twenty-five. He served the College under seven Presidents, and I
am sure that they all found him, as I did, considerate, firm but never
factious in opposition, and loyal in support. His religions opinions
were the quintessence of independence, and they were held with a
firmness which no influence, however near and strong, could shake.

336 PROCEEDINGS OP THE AMERICAN ACADEMY

In the conduct of his household he would owe no man anything.
Throughout a long life he was frugal and skilful in keeping his savin °-s.
His wants being simple, he thus earned the satisfaction of feeling
during the last twenty years of his life that he was fairly independent
in money matters, — a great satisfaction to a reserved and self-
respecting man.

Faithful, constant, candid, independent, — these seem to me some
of the high qualities of Joseph Lovering.

I ask leave, Mr. President, to second the resolutions you have
offered.

After President Eliot, the Corresponding Secretary, Pro-
fessor Josiah P. Cooke, addressed the Academy : —

I have been asked to speak of our late President as a teacher ; and
although I could wish that the duty had fallen to one who could por-
tray more forcibly his remarkable ability as a college and public lec-
turer, I feel that there is a certain fitness in the assignment, since I
have held intimate relations with him, first as pupil and afterwards
as associate, for more than fifty years. My acquaintance with him
began much earlier than his with me ; for, when quite a youth, I was
a constant attendant at his earlier lectures before the then recently
established Lowell Institute, which were at that time given in the Odeon
on Federal Street, near my father's home. From those lectures, con-
tinued several years in succession, I gained my earliest conceptions of
Mechanics, Electricity, and Astronomy. I can remember many of
the experimental illustrations as clearly as if the lectures had been
given yesterday, and it is a striking evidence of the lecturer's definite-
ness of statement and aptness of illustration that a young boy should
have been interested and instructed by lectures on subjects so abstruse.
These lectures were given on Wednesday and Saturday afternoons,
when there was a half holiday at school ; and I remember they were
well attended, although they were repetitions of lectures on the pre-
vious Tuesday and Friday evenings. At this time the elder Professor
Silliman was charming the Lowell Institute audiences by his brilliant
lectures on Chemistry, but Mr. Lovering did not suffer from the com-
parison ; and if the fascination arising from the fluency and wealth of
illustration of the elder man gave the bent to the boy's mind, he never
questioned who was the more instructive lecturer.

At this time, from eight to ten years after his. graduation from col-
lege and three to four years after his appointment as Hollis Professor
at Cambridge, Mr. Lovering did not give me the impression of a

OF ARTS AND SCIENCES. 837

young man, and through our long acquaintance he did not seem to age
until within the few last years. Of course such an impression largely
arises from the constancy of the mutual relations of men growing old
together ; but after making all allowance for the point of view, I think
it will still appear that our colleague, although a very young old man,
was a very old young man. As I look back I think this arose very
much from the absence of that nervous susceptibility which is such a
hindrance to most of us, and greatly increases the friction under which
we work. Professor Lovering's imperturbability was notorious with
all the graduates of the College during the last half-century. When
he lectured he never showed the least emotion, and in the class-room
his control of the muscles of his countenance was extraordinary. Not
many years after the period I have mentioned, I passed through the
regular course in Physics at our College, and I can see the Professor
now, sitting like an inquisitor on an elevated chair overlooking the
class, with his spectacles over the forehead, with the text-book, to
which he never referred, on the desk before him, and directing his
questions to one man after another in the clearest but most incisive
terms, and in the exact order of the book, without hesitation or failure
of memory. Each student was expected to take up the subject where
the last left it, and I still wonder at the feats of memory which en-
abled some of the class to repeat mathematical formulas, even differ-
ential equations, without the remotest intelligent knowledge of their
meaning. But although it was obvious that the Professor followed
every detail and noticed every inaccuracy, yet the most absurd blun-
ders and ridiculous incongruities never elicited a smile, or were any
further noticed than by calling up the next man. No direct instruc-
tion, not even any elucidation of the book, was ever attempted. We
did learn the book so far as it was intelligible to us, but nothing more.
We must not, however, judge such exercises by our present standards.
This formalism was the fashion in the education of the time, and the
all but universal rule in the College.

The dulness of the recitations was, however, at times enlivened by
the dry humor for which Professor Lovering was so noted among his
friends. An incident which he was fond of telling himself is very
characteristic, and recalls vividly those old college days. In the text
of Herschel's Astronomy, which was recited verbatim for many years
in the well known class-room at the south end of University Hall at
Cambridge, there is quite a full description of the seven asteroids
known at that time, and then follows a sentence something like this :
" Besides these seven, others will probably be discovered." One day
vol. xxvu. (n. 8. xix.) 22

338 PROCEEDINGS OF THE AMERICAN ACADEMY

a faithful but formal student gave it, " Besides these, seven others will
probably be discovered." The Professor, with his imperturbable
fixed gaze, simply asked, " Why seven ? " and called the next man.
The bull was afterwards several times repeated, and the Professor
had the credit of selecting his victims for the purpose ; but I have
also heard, what is more probable, that the class handed down the
joke, and that the repetitions were the result of collusion among
themselves.

The number of the asteroids now exceeds three hundred, and this
astounding development of Herschel's prediction is only of a piece
with what has passed in all departments of physical science. In the
middle of the century the question between the undulatory theory of
light and Newton's theory of emissions was still open, and in Brewster's
Optics, the text-book we studied, the weight of authority was given
to the latter theory. So also the different modes of energy were re-
garded as imponderable fluids, and a no inconsiderable part of the
text-book on Electricity was taken up with a discussion of the merits
of the then usually received theory of two electric fluids, as compared
with Franklin's theory of one. During Mr. Lovering's long life the
fundamental conceptions of physics entirely changed, and it was one
of his great merits as a teacher that he kept abreast of the times,
that he weighed systems impartially, and led his pupils to distinguish
clearly between ascertained facts and the systems of science by which
the facts are classified.

At the formal recitations I have described Mr. Lovering presided
as an officer of the College to enforce a prescribed task. He did not
consider that he was there to teach, in any proper sense of the term.
He had assigned an excellent book from which it was our duty to
learn, and from which we could learn, all of the subject we were
expected to know, and it was solely his duty to see that we did our
work. This does not seem to us now a very high ideal of a college
exercise, although doubtless the lazy men and the dullards did gain
an occasional idea from hearing their classmates' recitations. Still, it
must be remembered that this was the attitude of teachers in almost
all the class-room exercises of the period, and no one could have done
the duty assigned to him more faithfully or more impartially than
Mr. Lovering.

But if Professor Lovering, with most college teachers of his time,
did not feel it incumbent on him to give personal instruction in his
recitations, it was very different with his stated lectures. At these
he displayed his full intellectual strength, and I look back on them as

OF ARTS AND SCIENCES. 339

in many respects the most profitable part of my college course. He
was one of the best lecturers I have ever known, and I have known
the greatest masters of my time. He may not have had the imagina-
tion of Faraday or the grace of Dumas, but his lectures were instruc-
tive in the highest degree. The chief sources of his power are not
far to seek. In the first place, he had the great art of bringing his rea-
soning and his illustrations to the intellectual level of his hearers, with-
out belittling his subject. He was a popular lecturer in the very best
sense. He did not commit the common error of seeking to gain at-
tention through trivialities, or of attempting to appear learned by using
technical terms ; but he sought to raise his audience from their lower
plane to his level, and he succeeded to a wonderful extent. Again,
he had remarkable clearness of statement, and he gained this in the
only way it can be gained, by seeking definiteness of conception. He
did not trust to the inspiration of the moment to make a difficulty,
however familiar to him, intelligible to others ; but he laboriously
studied every subject he taught until he had a firm grasp of all the
concepts, and then the stream was clear because the spring was
clear. Lastly, Mr. Lovering had to a greater degree than I have
ever known, the power of looking at physical problems from different
sides, and seeing them in all their aspects. This gave him great fer-
tility in illustration, and often enabled him to present a subject from
a point of view wholly unexpected even by adepts in the science.

We often say in the laboratory, when troubled by the failures of a
faithful student, but unskilful experimenter, that a chemist, like a poet,
is born, not made, and the same must beequally true of a physicist ;
and if we consider only the power of original investigation, there is
doubtless much truth in this trite apothegm ; but it is not true of
many great scientific scholars and teachers, and of this Mr. Lovering's
success is a conspicuous example. In college he was one of the first
scholars of his class, but although a good mathematician his tastes
were linguistic and literary rather than scientific, and he had already
entered on the study of Divinity when a chance opening determined
his career in life. The opinion has often been expressed that the
intuitions and enthusiasm of an original investigator are necessary to
make a great scientific teacher, and if by this is meant necessary to
direct to the best advantage the studies of those born to the purple,
I should agree in the judgment. But, on the other hand, the devious
and narrow paths through which the investigator is constantly led in
the chase of natural phenomena are apt to give him a very limited
view, while the scholar who commands a larger field is better able to

340 PROCEEDINGS OP THE AMERICAN ACADEMY

point out to ordinary minds the extent and bearings of the numer-
ous details which it has required very many explorers to bring to light.
This was strikingly true of Mr. Lovering. He was not, as he him-
self would be the first to avow, a born investigator, although, as his
successor will doubtless tell you, he did very substantial work as an
original student ; but he was a great teacher, and I am persuaded
that the experiences of his education to which I have referred had an
important influence on the result. He came to the study of physics
as a ripe literary scholar ; and he dwelt on its various fields, with their
intricate relations, until he had acquired clear conceptions of the
whole ground, and it was thus that he gained the power of presenting
all the details with such clearness and force.

So called " original research " is now a fad in education, and we are
in danger of overlooking the fact that the scholar and teacher is no
less important to the community than the investigator. It is absurd
to contend which is the more important member of the body politic.
No one has pressed on this community more persistently than myself
the importance of scientific investigation, not primarily for the results
it may yield, but chiefly as a great influence towards sustaining the
higher life of the nation, and yet I feel assured that the explorers
would soon lose their reckoning were not there also a class of scholars
to co-ordinate their results and supervise their work. It is easy to
sneer at popular lectures, and I have as great a contempt as any one
for mere glitter and froth ; but the lecturer who can raise men to a
higher intellectual level confers a benefit on the community which is
none the less real because its effects may not be at once apparent.

Faraday was one of the very few men who was at the same time
a great teacher and a great investigator. I never was more impressed
by any intellectual achievement than by the popular, even juvenile,
lectures which I once had the privilege of attending at the Royal
Institution in London. And, however great the bequests of knowledge
this investigator left to mankind, I greatly doubt whether, when the
final account is closed, the greatest contribution of Faraday to human
welfare will not be found to be his popular lectures. It has been
well said that the greatest discovery of Sir Humphry Davy was
Faraday, — a mere bookbinder's apprentice when he was fascinated
by Davy's brilliant lectures, — and who can number the intellectual
offspring of the still greater teacher ? It is the misfortune of a col-
lege teacher that the successive classes pass on long before the fruits
of his influence have time to mature ; but the influence lives, and could
we trace the effects of our associate's work I am sure that we should

OF ARTS AND SCIENCES. 341

be satisfied that fifty years of devoted service has not been spent in
vain.

A substantial part of Professor Lovering's work as a teacher, which
we must not forget, are the numerous popular essays on scientific sub-
jects which he published from time to time in various periodicals.
Several of the earlier of these appeared in the " American Almanac,"
and most of the later in the Proceedings of this Academy, including
addresses on the presentation of the Rumford Medal, and biographi-
cal notices printed in connection with the Reports of the Council.
What is probably a complete list, as it was revised by Professor
Lovering himself, may be found in the " Popular Science Monthly "
for September, 1889, in connection with a short biographical notice.
In these essays, popular only in that they do not assume a specialist's
knowledge, are preserved to us the striking characteristics of Pro-
fessor Lovering's teaching to which I have referred. They are as
fresh to-day as when written, and are not only highly interesting as
choice examples of popular scientific exposition, but also of permanent
value, as exhibiting in a striking manner the changes in the modes of
scientific thought during the last half-century. I am anxious that
the most suitable of these essays for the purpose should be collected
and reproduced in a handsome volume, and in my judgment this
would be the most fitting memorial we could prepare of our late
honored President.

Professor John Trowbridge, the successor of Professor
Lovering as Director of the Jefferson Physical Laboratory
in Harvard University, nest spoke : —

In due time Professor Lovering's scientific labors will receive at-
tention in a more elaborate way than I can pretend to devote to them
to-night. His death is so recent that the time for the critical sum-
ming up of the labors of a long life has not been sufficient for a
careful presentation to you of the subjects in which he worked, and
upon which his reputation as a scientific man will rest. The subjects
of Astronomy, Meteorology, Magnetism, and Optics were favorite
ones with him. I find in the American Journal of Science a paper
on Meteoric Observations made at Cambridge in 1839. This paper
marks, I believe, the beginning of his scientific work, and following it
were a large number of articles on the subjects I have mentioned.
The catalogue of scientific papers published by the Royal Society
of England contains between the years 1839 and 1863 the titles of
eighteen papers. Among these are the following : —

342 PROCEEDINGS OF THE AMERICAN ACADEMY

On Magnetic Observations made at Harvard University. Memoirs

Am. Acad., 1846.
On Corona? and Halos. Proc. Am. Acad., 1848.

On the American Prime Meridian. American Journal of Science, 1850.
New Experiments and Modes of illustrating the Laws of Light and

Sound. Proc. Am. Acad., 1852.
On Motions of Rotation. Proc. Am. Acad., 1852.
On Donati's Comet. Proc. Am. Acad., 1857.
Memoir upon the Secular Periodicity of the Aurora Borealis. Proc.

Am. Acad., 1857.
On the Velocity of Light and the Sun's Distance. Proc. Am.

Acad., 1862.

This number of papers can be greatly increased by the addition
of his scientific essays and addresses. He also did much routine
scientific work in connection with the determination of longitude by
the Coast Survey, holding a position as Astronomer to the Survey
during the administration of Professor Benjamin Peirce.

The subjects of sound and light, and wave motion in general, I have
said, were favorite ones with him, and he took great pleasure in adding
to the Physical Cabinet apparatus to illustrate these subjects ; so that
to-day they form the most complete portion of the apparatus for
demonstration which he left to his successors. I remember that he
once showed me an apparatus which he had devised for obtaining the
velocity of electricity, which combined in an ingenious manner the
apparatus in sound with which he was so familiar and certain arrange-
ments of electro-magnets. It is doubtful whether Professor Lover-
ing's contemporaries, who occupied chairs of Natural Philosophy in
American colleges can show so large an amount of scientific work as
he performed in addition to his college exercises.

After listening to such appreciative words as we have heard from
those who have been the life-long friends of Professor Lovering, I feel
that my testimonial may seem scant. Those who attended his lectures
have a store of remembrances of his wise sayings, of his peculiar humor,
which often threw the light of a different philosophy from that which he
was professedly elucidating, and which showed that literary tendency
which made him capable of giving wise counsel over a wide range of
University matters. Strange to say I never heard one of his college
lectures, but I knew from conversations with him that he could present
a subject with a certain finish and fine deliberation which was the de-
spair of new beginners in the art of demonstration. I have seen him
prepare an experiment for a lecture with that patience which Balzac is
said to have devoted to his paragraphs, taking every possible care that

OP ARTS AND SCIENCES. 3-i3

the form in which the idea was to be presented should not break down
through that spirit of total depravity which sometimes seems to preside
over physical experimentation. Professor Lovering, imbued with a
philosophy of life which I am inclined to believe was one of his most
remarkable attributes, knew full well that this depravity of inanimate
objects was the expression of want of patience and thought in the ex-
perimenter, and he never hesitated to try an experiment scores of
times before its presentation at the lecture table.

All who enjoyed intimate friendship with him must have felt the
strength of this fine deliberation and careful conduct toward the forces
which shape our physical life. Acting with him on the Rumford
Committee, and sometimes on other committees, I have felt that in
voting with him I should be safely conservative, and the wisdom
which only a long life of great thought can give was apparent in
every deliberation.

Professor Lovering belonged to a school of Professors of Physics
which is very different from that which is now prevailing in our univer-
sities and technical schools ; for the laboratory method of instruction is
taking the place of the lecture method. It was hinted that he hesitated
to chancre the method which had been a life one with him. I doubt,
moreover, whether any one who had reached the age even of fifty, and
had never accustomed himself to laboratory work, would be willing to
enter upon the arduous and trying work of physical research. This work
must be undertaken chiefly by younger men. One could always take
one's results to Professor Lovering and have them illuminated by the
stores of his knowledge of the history of the subject. Professor Eustis
once remarked to me, that I should find Professor Lovering a very
sound man in his subject, and I verified this remark frequently. I
have spoken of the humor with which he often threw the light of phi-
losophy upon things animate and inanimate. A very egotistical stu-
dent was once giving his views to us at a seaside resort, and after his
departure Professor Lovering remarked that he was " all-sufficient,
self-sufficient, and insufficient."

In the course of a lecture he was contrasting the undulatory
theory of light with the corpuscular theory, and after stating with a
certain judicial manner the objections to the latter theory and leaving
it no ground to stand on, he finished it thus, in his slow, deliberative
tones : " The reason that the corpuscular theory is no longer advo-
cated is that all its advocates are dead."

Some men are compelled to assert themselves through the whole
course of their lives, for the world is not vividly conscious of their

344 PROCEEDINGS OP THE AMERICAN ACADEMY

presence in it. Professor Loveriug, however, had a marked personality,
which did not seem to require self-assertion. He was a marked man
in any gathering. Perhaps he gave the impression that he had con-
quered the world and could smile at its foibles, and one desired to catch
the secret of his self-possession, with the expectation of having it told
with humor. It seems to me that he resembled certain great philoso-
phers, and might be said to be a follower of Aristotle.

We all remember that his presentation of a subject had a certain
old-time stateliness of manner, which was perfect in the days when
oratory was much esteemed, and had not become affected by an age of
telegrams and telephone communications. I believe that a collection
of the essays of Professor Lovering on physical and astronomical sub-
jects would show that discriminating spirit and deliberative wisdom,
and that peculiar literary style, which characterized him, and which
must leave a permanent remembrance upon the minds of all who
knew him.

Still further tributes to the noble character and great
worth of our deceased President were made in the following
letters.

From Hon. Robert C. Winthrop.

My dear Dr. Peabody, — I regret extremely that age and
infirmities will prevent my attending the meeting of the Academy
to-morrow evening. It would afford me peculiar satisfaction to be
present at the commemoration of our lamented friend, Professor
Lovering, and to listen to the tributes proposed for the occasion.
His services as President of the Academy constitute but a small
part of his claim to consideration. His lifelong loyalty to the cause
of science, and his devotion to the University as Professor for
more than half a century, entitle him to a most grateful remem-
brance.

Nor can I forget my association with him, for several years
past, as one of the Trustees of the Peaborly Museum of Americau
Archaeology and Ethnology.

I say nothing of the pleasant relations which I enjoyed with
him as a friend, and of the respect which I have always enter-
tained for his character.

Believe me, with renewed regrets that I cannot attend the
meeting,

Yours, sincerely,

Robert C. Winthrop.

OF ARTS AND SCIENCES. 345

From Professor W. W. Goodwin, of Harvard University.

My dear Dr. Peabody, — I am very sorry that I cannot attend
the meeting of the Academy this evening in memory of Professor
Lovering. Of our late President as a man of science I have no
right to speak, for I can claim only to be one of the large class
of his admirers who viewed his scientific attainments from a re-
spectful distance. But I have known him for more than forty
years as a kind friend, and in later years as a genial companion ;
and by his death I have lost one for whom I felt deep respect and
warm affection.

I first knew Mr. Lovering as lecturer and teacher in Harvard
College. In 1849, when I first came under his instruction, he
was in his best vigor, and his lectures on mechanics, optics,
electricity, and magnetism always seemed to me perfect of their
kind, and admirably adapted to their purpose, which was to. give
a geueral knowledge of physical science to a whole college class,
who had no opportunity to study in detail more than a small
fraction of the sciences which his lectures covered. It seems to
lie beyond the province of our reformed College to give this gen-
eral view of the physical sciences, or indeed of any of the sciences,
to our students ; and perhaps we do not always remember that
the knowledge which every student had an opportunity to gain
from Mr. Lovering's lectures ought still to be brought within the
reach of every one at some stage of his education.

In the old College Faculty, as I first knew it in 1856, Profes-
sor Lovering was one of the most important and influential mem-
bers. He was constant in his attendance, and he always had a
decided opinion on every question that came up. He often de-
cided a long and wandering debate which had led to nothing, by
a few words of plain common sense, or even by a humorous re-
mark into which an argument was condensed. His drv humor
was second only to that with which that master of humor, Presi-
dent James Walker, constantly entertained and often convinced
the College Faculty. During a great part of the presidencies of
Mr. Sparks, Dr. Walker, Mr. Felton, and Dr. Hill, he held the
post of Regent, which has since been extended into the less regal
but more responsible one of Dean. A comparison of the Regent's
office in Mr. Lovering's day, open four hours a week, with the
present Dean's office, open nine hours a day, shows the growth
of the College, and also the changed relation of the students to

346 PROCEEDINGS OP THE AMERICAN ACADEMY

the officers of administration. In all the affairs of his office, Mr.
Lovering was exact and systematic to the last degree. His fixed
principles of college government, and his wonderful memory of facts,
names, and faces, enabled him to be perfectly consistent in all his
dealings with students, and his high standard of justice made it
almost certain that no one could be wronged by his decisions.
He was, indeed, a model executive officer, and his long adminis-
tration as Regent did much to establish and confirm the policy of
Harvard College for a period of twenty years.

I well remember one of the first occasions when one of the
speakers at a College exhibition uttered strong and decided anti-
slavery sentiments. One of the older Professors remonstrated to
Mr. Lovering, and exj)ressed his surprise that such a passage should
have been allowed to be spoken. Mr. Lovering replied, l( I have
heard the other side of that question here all my life; and I think
it is quite time that we heard this side now."

Mr. Lovering's sense of fairness was one of his most marked
characteristics. He was also a man of remarkable kindness and
sympathy, which often took the form of most efficient action even
when he seemed to try to repress its expression in words. His
whole personality was, indeed, a most striking one, which im-
pressed every one who met him, while it was fully appreciated
only by those who knew him best.

Regretting that I cannot listen to the tributes of respect which
will be offered to his memory this evening, I remain ever

Yours, sincerely,

W. W. Goodwin.

From Mr. Justin Winsor, Librarian of Harvard University.

My dear Dr. Peabodt, — Mr. Lovering's failure to be present
at a gathering of the Thursday Evening Club in Boston was so
unprecedented, that at the meeting which was held during his last
illness everybody remarked upon his absence, and it was the first
intimation most of us had that he was confined to his house.
A fortnight before, at its previous meeting, I had talked with
him about his constancy of attendance, and he told me that he
had never missed a meeting, and he was among the older mem-
bers of the Club. Even to the last he was ready to contribute
his share to the edification of its members, and he said to me on
this last meeting of his attendance, that he was ready to be called
upon for a paper, if there should at any time be a gap to be filled.

OF ARTS AND SCIENCES. 347

His enjoyment of the Club was in accordance with such a record
of unrivalled faithfulness. He was alive to every phase of intel-
lectual progress, and he found the surprises and novelties offered
to the club in such direction, often in advance of more public
enunciation, stimulating and enjoyable. He took much gratifica-
tion in the prompt response which was found among the members
of this Club, as well as among the officers and friends of the
University, when a testimonial was prepared for him on his re-
tirement from the active duties of his professorship. This move-
ment resulted in a dinner given to him in Boston, which was
presided over by the President of the University. Mr. Lovering
made a response to the principal toast, in which, with his peculiar
humor, he reverted to the events of his long career as a teacher.
Dr. Holmes referred to the extent of this career as only compar-
able in the history of the College to that of Tutor Flynt, and
suggested that a duplicate of that old preceptor's silver teapot,
which had come down to him by family lines, should make part of
the testimonial to Mr. Lovering. This reproduction was carefully
made, and Mr. Lovering a little later placed it among his house-
hold treasures with evident satisfaction. He was also asked to
sit for his portrait, and no sitter could ever have been more faith-
ful to the demands of the artist than he was, — prompt in his
place and never tiring. The picture which represents him in his
gown as a Professor, sitting full face, was placed in the parlor of
his house, ultimately to be transferred to the walls of Memorial
Hall.

Yours, sincerely,

Justin Winsor.

From Professor F. W. Putnam, of the Peabody Museum of American
Archaeology and Ethnology.

My dear Dr. Peabody, — On the day assigned for the memorial
meeting of the Academy in honor of its late President, Professor
Joseph Lovering, I was unexpectedly called out of town, and was thus
prevented from uniting with the other members in offering tributes
to his memory. Will you therefore permit me to express my appre-
ciation of one whom for over thirty years it has been my privilege
to count as a friend. '

At the time of my entering the Scientific School, in 1856, Pro-
fessor Lovering was in the prime of life, and it was my pood fortune
to attend his lectures. For eight years following, I often had the

348 PROCEEDINGS OP THE AMERICAN ACADEMY

pleasure of meeting him, and ever found him genial and ready to give
freely of his store of knowledge to an inquiring student.

In 1868-69, we were again intimately associated on the occasion
of his trip to Europe, when he delegated to me his position as Perma-
nent Secretary of the American Association for the Advancement of
Science, and the editorship of the Chicago and Salem volumes of Pro-
ceedings. Again, in 1872, when he was elected President of the
Association and resigned the office of Permanent Secretary, it fell to
my lot to succeed him in the Secretaryship.

This election to the Presidency was not only a unanimous offering
of the Association to a distinguished member, but also a merited
recognition of his long and faithful service as its trusted executive
officer.

Professor Lovering was the second Permanent Secretary of the
Association, and was elected in 1854 as the successor to Professor
Baird. He filled the position for nineteen years, and it is well known
by the older members that his efforts were unceasing in fostering the
objects of the Association. He fully believed in the benefits which
would accrue to American science from these annual gatherings of
scientific men in different parts of the country. In conversation on
this subject, he always expressed his firm belief in the important work
of the Association, and the advantage to be derived from this united
effort to encourage and develop scientific work by interesting hundreds
of cultured men and women in scientific objects, and by stimulating
isolated workers to greater exertion. Eminently social and agreeable,
he always took great pleasure in these gatherings of kindred spirits,
and was an almost constant attendant at the meetings until the last
few years of his life. His advice in the Council meetings of the
Association, while always somewhat conservative, was nevertheless
favorable to progress. His remarks were always earnest, but never
hasty or passionate, and were so sure to carry conviction that his
views of a subject generally prevailed.

For the third time we were brought into intimate official relations
when as President of the Academy, in 1888, Professor Lovering be-
came a Trustee of the Peabody Museum of American Archaeology
and Ethnology of Harvard University, as the successor of the late
Professor Asa Gray. In this office he was always prompt in attend-
ance at the meetings of the Board and often visited the Museum, in
which he was greatly interested.

While Professor Lovering was always serious in his work, and
when speaking upon important subjects, yet no one liked better than

OF ARTS AND SCIENCES. 349

he the moderate pleasures of life, or enjoyed sociability with a
greater zest.

Thus it has been my fortune to know this friend under many con-
ditions, and through all these years and varied circumstances, official
and social, I have never found him lacking in sympathy and readiness
to advise and assist in every way in his power, and there has never
been a ripple of antagonism to mar our friendship.

Although we deeply regret the loss of this dear friend from our
midst, it will always be a pleasure to cherish the memory of his
many virtues, his true friendship, his love for his fellow men, and his
devotion to science.

Yours, sincerely,

F. W. Putnam.

The resolutions were unanimously adopted by the large
company of Resident Fellows in attendance at the meeting.

Andrew Howland Russell, of Boston, was elected a Resi-
dent Fellow in Class I., Section 4.

Eight hundred and forty-eighth Meeting.

March 9, 1892. — Stated Meeting.

The Vice-President in the chair.

The Corresponding Secretary read letters announcing the
death of Sir William Macleay, of Sydney ; of John Couch
Adams, of Cambridge, England, Foreign Honorary Member ;
and of the Grand Duke Constantin Nicolayevitch, President
of the Imperial Russian Geographical Society. Letters were
received from Samuel J. Mixter and Warren Upham, accept-
ing Fellowship in the Academy.

The Vice-President announced the death of Henry Inger-
soll Bowditch, George Bassett Clark, Thomas Sterry Hunt,
William Raymond Lee, and Sereno Watson, Resident Fel-
lows ; and of George Washington Cullum and Noah Porter,
Associate Fellows.

On motion of the Corresponding Secretary, it was

Voted, To meet on adjournment on the 13th of April.

350 PROCEEDINGS OF THE AMERICAN ACADEMY

On motion of the Recording Secretary, it was
Voted, To amend Standing Vote 9 by substituting "eight"
for " half-past seven," so as to read : —

" 9. The annual meeting and the other stated meetings shall be
holden at eight o'clock, P. M."

The vacancy occasioned by the death of the President,
Joseph Lovering, was filled by the election of

Josiah P. Cooke, President.

Dr. Peabody, in relinquishing the chair, expressed the
pleasure he had experienced while serving as an officer of the
Academy, and intimated his intention of declining re-election
as Vice-President at the approaching annual meeting.

The President elect addressed the Academy as follows : —

I thank you most warmly for the very great honor you have con-
ferred by this election as your President, and I need not to assure
you that I shall work for the best interests of our Academy so long
as your favor and my health and strength permit. I have been
for nearly forty years a member, and for thirty-eight years I have
discharged the duties of one or another of your subordinate offices.
For nineteen years I have been your Corresponding Secretary, and
during that time have edited twenty volumes of your Proceedings and
Memoirs, — much more than one half of all the material published by
the Academy since its foundation. You can understand from this
what pleasure it will give me to finish this long period of service as
your presiding officer. Moreover, my associations with the Academy
go back before my membership.

It so happened that my honored father occupied for a long period
a law office at No. 9 State Street, adjoining that of John Pickering,
that noble man and learned scholar, who was your President from
1839 to 1846. Through the kindness of this great man, who warmly
encouraged a boy's scientific tastes, I had free access to his library
and the use of his books ; and it was there that I came to know that
there was such a learned society as the American Academy of Arts
and Sciences, and to indulge the thought that I might one day make
myself worthy to become a member of such an illustrious body. I
cannot but confess that the lustre has become somewhat dimmed with

OF ARTS AND SCIENCES. 351

use ; but my colleagues will appreciate how great a privilege I feel
it is to fill the place once held by this beloved patron of my youth,
and later by Jacob Bigelow, the good physician of my boyhood, and
by Asa Gray and by Joseph Lovering, my college teachers and the
warm friends of my manhood.

The President in the chair.

Dr. Seth C. Chandler presented a paper entitled, " Results
of Researches on Variable Stars." A discussion of this paper
followed, and remarks were made by Messrs. Searle, Edmands,
and Dolbear.

Dr. Henry Taber presented a paper entitled, " On a Theo-
rem of Sylvester's relating to Degenerate Matrices."

Eight hundred and forty-ninth Sleeting.

April 13, 1892. — Adjourned Stated Meeting.

The President in the chair.

The President read a letter from Captain Andrew H. Rus-
sell, accepting Fellowship in the Academy ; also, a circular
from the Executive Committee of the Congress of Engineers
and Architects at Palermo, inviting members of the Academy
to take part in its deliberations.

The vacancies in the Rum ford Committee, occasioned by
the death of Joseph Lovering and of George B. Clark, were
filled by the election of the following

Members of the Rumford Committee :
Edward C. Pickering, Charles R. Cross.

Dr. Seth C. Chandler presented a paper entitled, " Results
of Researches on Variations of Latitudes."

Professor Jackson presented, by title, a paper on the For-
mation of the Anhydrides of Benzoic and substituted Benzoic
Acids. By George D. Moore and Daniel F. O'Regan.

352 PROCEEDINGS OF THE AMERICAN ACADEMY

Eight hundred and fiftieth Meeting.

May 11, 1892. — Social Meeting.

The Academy met at the University Museum, Cambridge.

The President in the chair.

The President announced the death of August Wilhelm
Hofmann, of Berlin, Foreign Honorary Member of the Acad-
emy, and gave a brief sketch of his scientific work.

The following papers were read : —

Biographical Memoir of the late Sereno Watson. By
George L. Goodale.

On Bivalent Carbon. By John U. Nef.

Diamonds in Meteoric Iron. By Oliver W. Huntington.

The mineral cabinet of Harvard College was fortunate enough to
obtain, through the liberality of Francis Bartlett, Esq., one of the
two original masses of meteoric iron, weighing 154 pounds, brought
by Dr. A. E. Foote from near Canon Diablo, Arizona. As this iron
had been said to contain diamond, the following experiments were
made with a view of isolating if possible the diamondiferous material.
A mass of about one hundred grams' weight was dissolved in acid
assisted by a battery.

The iron was supported on a perforated platinum cone hung in a
platinum bowl filled with acid, and the cone was made the positive
pole and the dish the negative pole of a Bunsen cell. When the iron
had disappeared, there was left on the cone a large amount of a black
slime. This was repeatedly washed and the heavier particles col-
lected. This residue examined under a microscope showed black and
white particles, the black particles being mainly soft amorphous
carbon, while the composition of the white particles appeared less
easy to determine, though when rubbed over a watch-glass certain
grains readily scratched the surface.

The material was then digested over a steam bath for many hours
with strong hydrofluoric acid, and some of the white particles disap-
peared, showing them to have been silicious. Most of them, however,
resisted the action of the acid. These last were carefully separated
by hand, and appeared to the eye like a quantity of fine white beach
sand, and under the microscope they were transparent and of a bril-
liant lustre. A single particle was then mounted in a point of metal-
lic lead, and when drawn across a watch-crystal it gave out the
familiar singing noise so characteristic of a glass-cutter's tool, and

OP ARTS AND SCIENCES. 353

with the same result, namely, of actually cutting the glass completely
through. To verify the phenomenon, successive particles were used
for the purpose, and with the same result. The experiment was then
tried on a topaz, and the same little mineral point was found to scratch
topaz almost as readily as it did glass. It was finally applied to a
polished sapphire, and readily scratched that also, proving beyond
question that this residue of small, white, transparent grains must be
diamond, though no well formed crystals could be recognized.

Dr. Huntington then exhibited in the hollow of a watch-
glass the diamonds which he had obtained from the mete-
orite.

Catalogue of the Magnitudes of Southern Stars from 0°
to —30° declination, to the Magnitude of 7.0 inclusive. By-
Edwin F. Sawyer.

VOL. XXVII. (n. S. XIX.) 23

AMERICAN ACADEMY OF ARTS AND SCIENCES.

Report op the Council. — Presented May 24, 1892.

BIOGRAPHICAL NOTICES.

Edward Burgess By Alpheus Hyatt.

George Bassett Clark Arthur Searle.

William Prescott Dexter W. T. Russell.

Thomas Sterry Hunt William O. Crosby.

Joseph Lovering Josiah P. Cooke.

George Hinckley Lyman Henry W. Williams.

David Humphreys Stoker Samuel H. Scudder.

Cyrus Moors Warren Francis H. Storer.

Sereno Watson George L. Goodale.

George Washington Cullum .... William R. Livermore.

John C. Fremont George S. Boutwell.

Thomas Hill Andrew P. Peabody.

Joseph Leidy Thomas George Lee.

Noah Porter Andrew P. Peabody.

John Couch Adams Arthur Searle.

George Biddell Airy Arthur Searle.

Wilhelm Eduard Weber Amos E. Dolbear.

Notices of Bowditch, Lee, Lowell, Barker, Ferrel, Rutherfurd, Caligny,
Hofinann, and Ramsay are necessarily deferred to the next volume ; -while
those of Dexter, Fremont, and Leidy, deferred from last year, are given
below.

REPORT OF THE COUNCIL.

Since the Annual Meeting of the 26th of May, 1891, the
Academy has lost by death twenty-three members ; — eleven
Fellows, Henry Ingersoll Bowditch, Edward Burgess, George
Bassett Clark, Thomas Sterry Hunt, William Raymond Lee,
Joseph Lovering, James Russell Lowell, George Hinckley
Lyman, David Humphreys Storer, Cyrus Moors Warren, and
Sereno Watson ; six Associate Fellows, Fordyce Barker,
George Washington Cullum, William Ferrel, Thomas Hill,
Noah Porter, and Lewis Morris Rutherfurd ; and six For-
eign Honorary Members, John Couch Adams, Sir George
B. Airy, Anatole Francois Hiie Marquis de Caligny, August
Wilhelm Hofmann, Sir Andrew Crombie Ramsay, and Wil-
helm Eduard Weber.

RESIDENT FELLOWS.

EDWARD BURGESS.

Edward Burgess was born, June 30, 1848, at West Sandwich,
Mass., and graduated at Harvard in the class of 1871. During his
college life he studied natural history successfully, and was extremely
foud of yachting, showing in this way the forcible working of the two
dominating tastes that he afterwards carried to successful issues when
it became important to follow them out with practical assiduity. He
became Secretary and Librarian of the Boston Society of Natural
History by election on February 21, 1872, and continued to hold these
offices until May 2, 1888, when he resigned to devote himself wholly
to the profession of a naval architect. He died at Boston, July 12,
1891.

His scientific work never engrossed his whole attention, as did the

358 EDWAKD BURGESS.

study of the best construction of sailing vessels, but his work was of
the highest excellence in certain directions, commanding the respectful
attention of men of the first rank in all parts of the world.

Samuel H. Scudder, the eminent entomologist, speaks in his obitu-
ary notice of Burgess with such authority that we have done little
besides follow him in this brief article.

Soon after his connection with the Society of Natural History began,
he commenced to work in collaboration with Mr. Scudder upon the
abdominal appendages of New England butterflies, the results of
which were published in Scudder's celebrated volumes on those ani-
mals. This was followed by a joint work published by these two au-
thors upon the similar organs of the different species in the Thanaos.
He subsequently published a series of anatomical papers beginning
with an investigation of the structure of the head and of the mouih
parts in the Psocidse. The most important and valuable was that
upon the anatomy of the Milkweed Butterfly. Mr. Scudder says of
this : " In the text and plates accompanying the larger memoir he gave
a more precise and detailed account of both the external and internal
anatomy of the insect discussed than had ever been given before of the
anatomy of any perfect butterfly, and brought to light a number of
interesting points that had been nearly or quite overlooked before,
such as the nature of the stria? on the scales, the musculature of the
tongue and its intimate structure, the cuticular processes of the food
reservoir, the backward course and chambered enlargement of the
aorta within the thorax, and the false claspers of the male abdomen, a
remarkable series of new observations to have been made ujxm a single
insect."

His discovery of the strange course of the aorta in this butterfly led
him to pursue the subject further by the dissection of a number of
lepidopterous insects, and to embody its results in a brief illustrated
paper in the Proceedings of the Boston Society of Natural History
in the following year, by which he showed " that, if we except the
peculiar course of the anterior branch (of the aorta) in the hawk-moth,
we have (in the Lepidoptera) a gradual series from the butterflies
downward. In the former a distinct horizontal aortal chamber is pres-
ent ; in the higher moths a vertical node replaces the chamber, and this
vanishes in the lower moths."

His discovery of the curious locked up mouth of the larva of
Dysticus in an animal previously supposed to have been mouthless
followed this in the same year, and his anatomy of the grasshopper,
Anabrus, and of the moth, Aletia, followed each other in succes-

EDWARD BURGESS. 359

sion, and all of them were executed with such skill in every respect
as to command the attention of entomologists in every part of the
world.

He was considered an authority upon the Diptera, and his collection
of these animals contained fourteen thousand specimens. He however
published but little, although he had really done a large amount of sys-
tematic work upon this order.

His favorite recreation in the summer time was yachting ; and while
engaged in this apparently aimless occupation, he was really studying
the construction and handling of vessels, and following out a natural
bent leading to the development of the best and highest qualities of
his mind.

The services he rendered to natural history, although of high ex-
cellence, were not unique, whereas it may be said with confidence that
his work in naval architecture was a reform of the first magnitude.
Constructors worked empirically and were not able to produce im-
provements in any two consecutive boats which would show the
certain working out of results by means of a scientific method. Bur-
gess applied the discipline his mind had gained from the study of sci-
ence to the problem of boat building, and demonstrated the fact that a
system could be invented and used which would give certain results.

Knowing Mr. Burgess personally, and occupying for many years the
same office with him, also having some acquaintance with the subject
and its difficulties, it amazed me to see the modest confidence he pos-
sessed in his own application of scientific methods to this problem.
His replies to my questions, on two successive occasions following the
first victory in the international races, invariably disclaimed any great
merit on his own part, or any certainty that he could construct a better
model than his rivals, and he was fond of ending the argument by a
highly characteristic remark, — "A scientific method and experience
ought to enable me to beat myself."

The spirit of the scientist was dominant in him, and even during
times of the highest excitement I never knew him to admit that he
desired his boat would win in the international races. He always
insisted that he hoped the best model would win, declaring that the
object to be attained was the highest excellence in naval construction,
and this was to him more important than any other. It is a matter of
serious regret to his friends, and perhaps a great loss to the world, that
he never reached the goal of his desires, — an opportunity to apply his
methods and test their value on a large scale in the construction of first-
class steamers.

360 GEORGE BASSETT CLARK.

Personally, Edward Burgess endeared himself to all closely asso-
ciated with him by his uniform good nature and fairness. He never
plumed himself in the slightest degree upon his successes, and the pub-
lic adulation which crowned him after the international races was re-
ceived with gratification, but did not in the least disturb his equability
or increase his self-esteem. His untimely death was a national loss, for
there is no doubt among those that knew him that he was capable of
steady progressive development, a quality of body and mind which, in
combination with genius, gave strong assurance of a future greater even
than the past.

GEORGE BASSETT CLARK.

George Bassett Clark was born in Lowell, Mass., on February
14, 1827. His early education was received at the Grammar School,
the High School, and afterwards at Mr. Whitman's private school in
Cambridge, to which place his father had removed in 1835. In 1844,
the subject of this notice entered Phillips Academy at Andover,
where he completed his literary education, and began for himself an
original course of practical training in the work which was subse-
quently to distinguish him. He had already shown an interest in the
mechanical arts, and had made his proficiency with the lathe a source
of some little profit to himself, by manufacturing toys for his juvenile
acquaintances. He now procured a piece of an old bell, which he
took home with him, and from which he undertook to construct the
speculum of a reflecting telescope. Undeterred by the doubts of his
elders as to the possibility of bringing his scheme to a successful con-
clusion, he presently gave them a practical proof of his ability by
producing an instrument with which a satisfactory view of Jupiter and
its satellites could be obtained. This first success encouraged him to
attempt the construction of refracting as well as of reflecting tele-
scopes ; and his father, becoming interested in his son's experiments,
was thus led to join him in the work. Neither the father nor the son,
however, seems at this time to have expected seriously to undertake
the business of an optician. Mr. Alvan Clark continued to employ
himself as a portrait-painter, while the younger man, after finishing
his course at the Phillips Academy, engaged in the work of civil en-
gineering, and was employed in that capacity upon the Boston and
Maine and the Ogdensburg and Lake Champlain Railroads.

The discovery of gold in California, in 1848, turned his attention
to still another industry, and he was among the first who hastened to
the new land of promise. His fortune differed little from that of the

GEORGE BASSETT CLARK. 361

greater number of his fellow emigrants, and, after several months of
adventure and hardship, he returned, richer in experience than in
worldly goods. In his journey to California, he crossed the Isthmus
of Panama in the manner then customary, by a boat voyage up the
Chagres River and by difficult paths across the hills beyond. On one
occasion, his guides, whose language he could not speak, armed him
and themselves with clubs, and set out with him upon an expedition
the purpose of which he could not conjecture. It appeared that their
object was peaceable, being only to obtain a supply of provisions in
the way of legitimate trade, but that the clubs were necessary to de-
fend the party against the dogs who had to be encountered before the
trading could begin. In California itself provisions were still more
difficult to obtain, and when obtained were of the worst quality ;
moreover, the first part of the return voyage was attended by many
depressing circumstances. The excitement of travel and adventure was
probably overbalanced in Mr. Clark's mind by the painful impression
made upon his kindly nature by the scenes which he had witnessed,
for in after life he appeared to dislike recalling the incidents of his
expedition.

Upon his return, he resumed the work which had most interested
him in his boyhood, and opened a shop in East Cambridge for making
and repairing instruments. He was soon joined in this business by
his father and by his younger brother, although his father still kept
his Boston studio open for several years. Mr. George B. Clark's
personal history from this time is in great measure that of the firm of
Alvan Clark and Sons, which he had been so largely instrumental in
founding. The business was continued in East Cambridge until 1860,
when it was removed to the situation in Cambridgeport where it is
still conducted.

While Mr. George B. Clark was thoroughly familiar with the
purely optical portion of the work undertaken by the firm, the part
of that work which ordinarily depended chiefly upon him was that of
providing the mountings of telescopes, and of planning and making
the metallic parts of scientific apparatus of various kinds. In this
work he was highly ingenious, and his ingenuity was, if possible, sur-
passed by his perseverance. He was frequently called upon to contrive
means for the execution of new plans which had occurred to men of
science, and he could not be defeated by the mechanical difficulties,
which were often great, in the way of the desired result, when he had
once assured himself that the principles involved in the plans were
correct. With a mere verbal description, or at most, a rough sketch,

362 GEORGE BASSETT CLARK.

of the instrument required, he would readily undertake the solution of
the frequently perplexing problems which presented themselves when
its actual construction was begun. When it was finished, he was
equally indefatigable in experimenting with it, not only before it left
the workshop, but after it had been delivered to the purchaser, until
it had been brought into such condition as fully to answer its purpose.
He was indifferent to the mere external appearance of his work, but
spared no pains to make the results to be obtained with it as perfect
as possible.

Upon the criterion laid down by Solomon, few men have ever been
as well qualified as Mr. Clark to stand before kings ; for he was pre-
eminently a man diligent in his business. This virtue, no doubt, had
the corresponding defect, that he was almost incapable of allowing
himself reasonable time for rest and recreation. The holidays of his
workmen were usually spent by him in solitary labor, directed to
testing and improving the instruments in course of construction, or in
consultation with some scientific customer upon the best means of
evading the difficulties which were hindering the execution of some
new plan. When an important order was in the hands of the firm,
he could not rest till the work was accomplished. Thus, when the
instruments for the national observations of the transit of Venus in
1874 were to be constructed, and, owing to delay in the receipt of
definite orders the time for their execution was very limited, Mr.
Clark labored so unremittingly to accomplish what was required that
as soon as the instruments were sent off he was prostrated by illness,
from the effects of which, it is apprehended, he never fully recovered.
Still, notwithstanding weariness and imperfect health, the remainder
of his life exhibited the same continuous industry which had previously
marked it. During this period, the equipment of the Observatory of
Harvard College was largely increased. Numbers of new instru-
ments applicable to new forms of observation were called for from
the firm of Alvan Clark and Sons ; and Mr. George B. Clark devoted
to supplying these needs, not merely the attention due to a customer,
but the interest of a friend. Such men will always be overworked,
for their willingness and ability naturally overwhelm them with calls
for their assistance.

To enumerate the important instruments in the construction of which
Mr. Clark took part would be merely to give a list of the celebrated
telescopes and other pieces of apparatus which have been furnished
during the last forty years by the firm of Alvan Clark and Sons. But
attention may be called particularly to those instruments in which in-

WILLIAM PRESCOTT DEXTER. 363

genuity of metallic construction was especially necessary ; for this,
as has been said, was the province in which Mr. George B. Clark's
abilities were most marked. When the gearing required in the appa-
ratus for determining the velocity of light, constructed for Professor
Newcomb, proved to be soon worn out by the rapidity of revolution
required, Mr. Clark succeeded in applying the necessary remedy by
introducing raw hide into a certain part of the apparatus, instead
of metal. Among the instruments made for Harvard College Ob-
servatory and other institutions of Cambridge and Boston, in the
construction of which his skill and zeal were peculiarly advantageous,
may be mentioned several large spectroscopes, photometers, and pho-
tographic instruments.

The singularly genial and kindly temperament which Mr. Clark in-
herited from his beloved father insured him cordial regard, and even
affectionate sympathy, among a wider circle than that of his immediate
relatives and associates. His face and manner bore a stamp of refine-
ment of feeling which would not have been expected in a man whose
education and whose occupations were of so exclusively practical a
character. His incessant devotion to his business left him no leisure
for those pursuits which are traditionally regarded as tending to pro-
mote gentleness as well as gentility ; but nature had supplied him in
this respect with more merit than most men can acquire by training.

He was married in 1857 to Miss J. M. Mosely, who survives him ;
but he left no children. Although the failure of his health had for
several years been evident, his death by apoplexy on December 20,
1891, found him still busy with his work. His memory will be
cherished by all who knew him, and the instruments which he
planned will long testify to his skill by the scientific results which
they furnish.

WILLIAM PRESCOTT DEXTER.

William Prescott Dexter was the son of Franklin Dexter and
of Elizabeth, daughter of Judge William Prescott. He came of dis-
tinguished ancestry. His great-grandfather on the mother's side com-
manded the American troops at Bunker Hill. The historian William
Hickling Prescott was his uncle. His grandfather, Samuel Dexter,
was an eminent statesman. Both his grandfathers were members of
this Academy, and they held high rank as lawyers, as did his father
also. All of them were prominent citizens. So too was his distant
kinsman, Aaron Dexter, M.D., likewise a member of this Academv.

364 WILLIAM PRESCOTT DEXTER.

who held the Chair of Chemistry and Materia Medica in Harvard
College from 1783 to 1816, and was thenceforth Professor Emeritus
until his death in 1829.

When thirteen years old, William P. Dexter passed from the Boston
Latin School to Harvard College, and was graduated thence in 1838,
and from the Harvard Medical School in 1842. He established him-
self as a practising physician, first in Boston and then in Brookline,
and devoted himself to this profession during a number of years. In
1847 he married Margaret Austin, daughter of William Austin, lawyer
and essayist, always to be remembered in American literature as the
author of " Peter Rugg, the Missing Man."

The following sketch of Dexter's after life has been furnished by
his friend, Dr. William J. Russell, of London.

William Prescott Dexter was born at Boston, on the 10th of Decem-
ber, 1820. He studied medicine at Harvard College, and graduated in
1838. After leaving college, he practised medicine at Brookline for a
few years, but his strong interest in pure science and his longing to
devote himself solely to scientific pursuits made him feel the irksome-
ness of the ordinary routine of a medical practitioner's life, and induced
him to give up the medical profession, and to go abroad in order to
study chemistry. From this time to the end of his life he devoted
himself entirely to the prosecution of that science. His interest in
and devotion to chemistry never flagged, and although he did not re-
side permanently in any one place, but lived in different parts of
Germany, in England, and occasionally returned to America for a
short time, still his one great interest in life was the study of chemis-
try, and wherever he settled for any length of time he always had a
laboratory. Few there are who have devoted their lives so entirely
to science simply for its own sake. No desire for place or for emolu-
ment stimulated Dexter's love for chemistry ; it was a pure desire to
increase knowledge and to learn with rigorous accuracy the true
nature of the phenomena he was interested in. In organic chemis-
try he took comparatively little interest ; the theoretical conceptions
which play so important a part in this branch of chemistry he was
loath to admit, and he did not sufficiently believe in them to be inter-
ested by them ; but it was in inorganic chemistry, and especially in the
analytical branch of the science, that his whole interest was centred.
Rose's Analytical Chemistry was ever a book of fascinating interest to
him. He studied it when in America, when he had little or no means
of carrying out its precepts, and it was this book which induced him
to give up his professional career and go to Germany, and it was to

WILLIAM PRESCOTT DEXTER. 365

Rose's laboratory in Berlin that he first went. Even before leaving
America, and while still in practice, he revised and published in 1850,
in a separate form, the tables for the calculation of analyses which
were appended to Rose's work. This entailed a very considerable
amount of labor ; for the tables were most thoroughly revised, and
nothing but the most perfect accuracy would satisfy him ; and he
tells us in the Preface, that " every calculation was performed by
myself both by direct division and by the use of logarithms." Also
extraordinary care seems to have been taken to avoid all errors of the
press.

After working for some length of time in Berlin, Dexter went to
Gottingen and worked in Wohler's laboratory, and from Gottingen
he went to Heidelberg. Here he worked for about twelve months in
Professor Bunsen's laboratory, and it was during this time that he
carried out his most important published work, his determination of
the atomic weight of antimony, which was published in 1857. This
work was admirably carried out. The writer well remembers the care
and thought bestowed upon it, how every possible error he could con-
ceive of was considered and eliminated, and the wonderful accuracy
with which the manipulation was performed. The method first tried
was the simple one of precipitating the antimony by gold ; but this
method was found to give inaccurate results, and was abandoned, and
the direct oxidation of the metal substituted. Other chemists were
working on the same subject at this time, two of them, Dumas and
Kessler, obtaining results very nearly agreeing with Dexter's num-
ber, 122.34; but Schneider obtained the number 120.3. These
researches led to the adoption at that time of the number 122.0.
Since then further researches have been made. Cooke in 1880 pub-
lished a very elaborate and thorough investigation of the matter. Other
investigators and other distinct methods have confirmed the lower num-
ber, and 1 20 is now generally adopted as the true atomic weight of
antimony. At the same time, it is difficult to see where the error, if
there be one, crept into Dexter's experiments. All the papers which
Dexter published related to analytical chemistry, some appearing in
Poggendorf's Annalen, and some in the Proceedings of the Ameri-
can Academy and in the American Journal of Science. His inter-
est and his special ability lay in analytical chemistry. He was one of
the most perfect manipulators who have ever lived ; the precision and
accuracy with which he performed the different processes of analysis
were astonishing. Every step was thought out, and then performed as
carefully and intelligently as possible. Of late years the discovery of

366 WILLIAM PRESCOTT DEXTER.

a perfect method, and consequently one of general application, for the
estimation of phosphoric acid, engrossed entirely Dexter's attention,
and for many years he was considering and experimenting on this
subject. The subject had an extraordinary fascination for him. No
difficulties, and he met with many, could daunt him, and he has left
behind much work of a very interesting and high kind on this subject.
At last he seems to have discovered a method which would satisfy
even his exacting requirements, but unfortunately he did not live to
complete his work. The introduction to it he had worked out, in the
form of a most rigorous examination of the methods now in use, and
the degree of accuracy of which they are susceptible, but the com-
pletion of his method remains unfinished. During the last few years
of his life he settled in Leamington, England, and led there a peaceful
life, making the best room of his house into a laboratory, and devoting
himself to the study of analytical chemistry, and amusing himself with
some practical problems in higher mathematics. He died on the 8th
of November, 1890.

Papers by William Prescott Dexter.

1. Renal Calculus. Passage through the Ureter, assisted by the Use of

Ether. Boston Medical aud Surgical Journal, 1S49, XL. 219.

2. Tabulae Atomicse : The Chemical Tables for the Calculation of

Quantitative Analyses of H. Rose. Recalculated for the more recent
Determinations of Atomic Weights, and with other Alterations
and Additions, by William P. Dexter. Boston, 1850, 8vo, pp. 70.
3 Ueber die Trennung der Thonerde vom Chromoxyd. Poggendorf's
Annalen, 1853, LXXXIX. 142.

4. Ueber die Trennung der Wolframsaeure vom Zinnoxyd. Poggen-

dorf's Annalen, 1854, XCII. 335.

5. [Analysis of Polyhalit.] Reported by H. Rose, Bericht der Aka-

demie der Wissenschaft zu Berlin. 1854, p. 412.

6. Ueber das Atomgewicht des Antimons. Poggendorf's Annalen,

1857, C. 563.

7. On the Double Salts of Cyanide of Mercury. Proceedings of the

American Academy, V. 355. (9 Dec, 1861.)

8. Remarks upon the recent Determinations of the Atomic Weight of

Antimony. Proc. Amer. Acad., V. .359. (14 Jan., 1862.)
9 On the Aluminates of Baryta. Proc. Amer. Acad., VI. 97. (28
Jan., 1863.)

10. Obituary Notice of Heinrich Rose. Proc. Amer. Acad., 24 May,

1864, VI. 312.

11. On the Preparation of Hydrofluoric Acid. American Journal of

Science, 1866, [2.], XLII. 110.

THOMAS STERRY HUNT. 367

12. New Chemical Apparatus. American Journal of Science, 1868, [2.],

XLVI. 51.

13. On the Sulphates of Oxide of Antimony. American Journal of

Science, 1868, [2.], XLVI. 78.

14. Obituary Notice of Dr. Augustus Matthiessen. American Journal of

Science, 1871, [3.], I. 73.

THOMAS STERRY HUNT.

The subject of this notice, whose death occurred in New York
City, February 12, 1892, made extensive contributions to American
science, and has permanently identified his name with its progress
and development. Choosing two of the most rapidly advancing
sciences, chemistry and geology, as his field of work, and studying
these especially in their intimate and extensive interactions, he had a
large and honorable share in giving form to our present knowledge
upon these subjects. Although an indefatigable experimenter and an
extensive observer, Dr. Hunt was also eminently an original and
philosophic thinker, and took an influential part in the establishment
of the most matured scientific theories.

Thomas Sterry Hunt was born in Norwich, Conn., on September 5,
1826. His ancestor, William Hunt, was one of the founders of Con-
cord, Mass., in 1635. His maternal grandfather, Consider Sterry, of
Norwich, was a civil engineer and mathematician, and was the au-
thor of text-books of arithmetic and algebra published one hundred
years ago.

While the subject of this sketch was a child, the family moved to
Poughkeepsie on the Hudson. There the father died when Thomas,
the oldest son, was twelve ; and the mother returned with her family
of six young children to the old home in Connecticut. For a short
time Thomas attended the public school ; but it was for a short time
only, as he thus early was required to share the burden of the family
support, and to seek employment.

At that time his intention was to study medicine. Under the
counter of the store in which he was employed he kept a skeleton, as
well as his home-made chemical apparatus. Two local physicians
assisted the brilliant boy, thus educating himself, by the loan of books.

In 1845 he went to New Haven during the meeting of the Associa-
tion of Naturalists and Geologists, and obtained work as a reporter on
a New York paper. But a more important issue of this trip was a
visit to the elder Silliman, whom the boy had met in Norwich after

368 THOMAS STERRY HUNT.

one of the Professor's lectures. Struck by his precocious proficiency
in chemistry and mineralogy, Professor Silliman facilitated his ad-
mission to Yale College. Erelong he became paid assistant to Pro-
fessor Silliman, Jr., who was then making an extended series of water
analyses, in which Hunt aided him, and was admitted a member of
his household. The struggle for a livelihood had ceased.

While at Yale, between his eighteenth and twentieth years, he con-
tributed eighteen papers to Sillimau's Journal, and wrote the Organic
Chemistry for Silliman's First Principles. In the Preface to the first
edition, published in December, 1846, Professor Silliman acknowl-
edged the aid rendered by his young colleague as follows : " The
author takes pleasure in acknowledging the important aid derived
in this portion of the work from his friend and professional as-
sistant, Mr. Thomas S. Hunt, whose familiarity with the philosophy
and details of chemistry will not fail to make him one of its ablest
followers."

In 1847, while preparing to continue his studies in Great Britain,
he was appointed to a position on the Geological Survey of Ver-
mont, under Professor C. B. Adams, but soon resigned to accept a
similar position on the Canadian Survey. In February, 1847, he
entered on his duties as Chemist and Mineralogist to the Geological
Survey of Canada, taking possession of that small study and still
smaller bedroom opening off the Laboratory in St. Gabriel Street,
Montreal, where for so many years he, without any laboratory assist-
ant, not only did the routine analytical work of the Survey, but made
many experimental investigations in chemical geology. His literary
activity was prodigious, as evinced not only by the scope but by the
number of his contributions, no fewer than seventy-six articles ap-
pearing under his name in the Second Series of Silliman's Journal
alone. It was at this time that he conceived and published those wide
views on chemical and general geology which were embodied in the
greater works of his later years. His strictly official work as Chemist
and Mineralogist would have been more than enough for most men ;
but he supplemented it by spending several months of each year in
the field, and by assisting his chief, Sir William Logan, in the literary
and administrative work of the Survey. Every year from 1856 to
1862 he spent the spring months in Quebec, lecturing on chemis-
try in the French language before Laval University ; and for four
years he filled the Chair of Applied Chemistry and Mineralogy in
McGill University, at Montreal. In 1872 he resigned his position on
the Geological Survey of Canada, after a service of twenty-five years,

THOMAS STERRY HUNT. 369

to accept the Chair of Geology at the Massachusetts Institute of Tech-
nology, which lie held until 1878.

His eminence in science was early recognized by his election, in
1859, as a Fellow of the Royal Society of London, where for some
years he enjoyed the distinction of being the youngest Fellow. Early
in his career Harvard conferred on him the degree of M. A., and Laval
that of LL. D. ; and in 1881 the University of Cambridge, England,
also honored him with the degree of LL. D. The names of home and
foreign societies which enrolled him on their honor lists would fill
a page. He was a member of the National Academy of Science ; was
Acting President in 1871 of the American Association for the Ad-
vancement of Science ; and President in 1877 of the American Institute
of Mining Engineers. He was the first President by election of the
Royal Society of Canada, and held office at every meeting of the In-
ternational Geological Congress which his health permitted him to
attend. His influence at these important conferences was heightened
by his perfect familiarity with the French language.

What he considered his most important contributions to science up
to 1886, he embodied in two volumes, " Chemical and Geological Es-
says " (1874), and " Mineral Physiology and Physiography " (1886).
His mature views on the nature and effects of Chemism he published
in 1887, under the title of " A New Basis for Chemistry"; and he
applied the same principles to Mineralogy in his latest work, " Sys-
tematic Mineralogy" (1891), based on a natural classification.

From this incomplete sketch of his tireless and many-sided activity
we can form some idea of his learning and of his industry. He never
knew what it was to be idle, and never wasted his power on irrelevant
and desultory work, and thus he became the master of many sciences.
He was a good mathematician. Although not himself a profound
physicist, he was able to appreciate the more recondite results of
modern physical investigations. He felt very keenly those ineffable
affinities which bind every energy in nature to one central force, and
had a lofty conception of the interdependence of the laws of the uni-
verse, and of the harmonious blending therefor of chemistry and
physics.

As a geologist, Hunt's original work, whether in the field or in the
laboratory, was done among the crystalline rocks. He received his
geological training from the Director of the Canadian Survey, Sir
William E. Logan ; and his text-books were the Azoic rocks to the
north of the Lakes and the St. Lawrence, and the Palaeozoic rocks of
southeastern Quebec. To the knowledge of the stratigraphy thus
vol. xxvn. (n s. xix.) 24

370 THOMAS STERRY HUNT.

gained he added, from his store of chemical and mineralogical knowl-
edge and from his laboratory investigations, the facts and hypothetical
deductions which appeared to him to give as conclusive probabilities
to the life study of those older barren strata as the evolution of vege-
table and animal orgauisms gives to the history of later rocks. He
combined in his intellectual equipment the practical experience of a
field geologist with a theoretic erudition in geology and allied science
such as few of his fellow workers could claim to possess. He was
therefore warranted, as the area of his geological view grew, in shift-
ing his ground on certain subordinate points. The most notable in-
stance of such a change of position was that taken in his Presidential
address before the American Association for the Advancement of
Science, in 1871, when he subdivided the crystalline rocks which had
been previously classed as Laurentian and Huronian into six groups,
and altered the stratigraphic relations of what was known in the Can-
adian Survey as the Quebec Group. Whether the subject was im-
portant enough to warrant the vehemence with which he maintained
his ground and sustained his argument may, perhaps, be doubted ; but
to Hunt truth was truth, and the relative proportion and importance
of the truth had no weight with him.

It is not on his work as a stratigraphical geologist that Dr. Hunt's
fame will mainly rest ; but on his achievements in lithology and chem-
istry, and on the broad generalizations which he drew as to the early
development of the earth. There are essays in his second series, elab-
orating the crenitic theory, which rise to a high pitch of eloquence,
and which any one of literary tastes, though utterly ignorant of science,
will read with rapt enjoyment. Last year, after completing his " Sys-
tematic Mineralogy," and when so feeble that he could only move
from his bed to his desk, he commenced a book entitled " The History
of an Earth," in which it was his purpose to expand, in a connected
treatise, his splendid generalizations on stellar and telluric chemistry,
and especially to trace the influence of water under heat and pressure
in decomposing the primitive basic crust of the earth, and in creating
out of the primary elements the older crystalline rocks, and again
in re-creating from their sterile ashes, through decay and death, the
newer life-supporting and life-entombing strata which contain, written
in generation after generation, the newer history of the earth. But
death frustrated this and other literary projects.

Chemistry was Hunt's first love, and he never deserted her.
When he studied geology, his impulse was to seek below the visible
results of mechanical causes for the all-pervading chemical forces and

THOMAS STERRY HUNT. 371

agencies which, by dissociation and combination, by integration and
disintegration of elemental matter throughout all space, are building
up other worlds, as they built up ours. In his system of mineralogy
neither outward resemblances, nor similarity of crystalline structure,
nor possession of common elements, but the relation of hardness to
condensation, and the further relation of these qualities to chemical
indifference, constituted the basis for his classification of mineral
species. Whether amidst such a multitude of individual species he,
in his first arrangement, assigned to each its proper place, may well be
doubted, without questioning the substantial correctness of the princi-
ple on which his chemical and natural-historical classification rests.
Yet it is impossible to follow, in his " Systematic Mineralogy," the
beautiful progressive series of quotients deduced from the formula
V = p -+■ d (V being the coefficient of condensation, p the chemical
equivalent, and d the specific gravity), as calculated for the species
under each genus, without being convinced that Hunt heard and ex-
pressed one of those wonderful harmonies of which it is granted to but
few mortals to catch the theme, amid the complexity and often appar-
ent discord of nature's contending voices.

The doctrine of the equivalency of volumes, as applicable to liquid
and solid species, as well as to the gases, on which is founded Hunt's
" Natural System of Mineralogy," had dawned on his mind very early
in his chemical studies ; but its larger significance was revealed to
him only toward the close of his life. To him the domain of chem-
istry was much wider than it had been held to be under the old con-
ventional theory, which drew such precise lines between chemical and
mechanical forces. Like most philosophical chemists of to-day, he re-
garded all solution as chemical union, and all chemical union as nothing
else than solution. In his view all precipitation and all crystallization
from solutions involve chemical change, and all chemical species may
theoretically exist in a dissolved state, from which they pass into
polymeric mineral species, often insoluble. Regarding the same sub-
stance in its different polymeric states, due to different degrees of
condensation, as representing so many different chemical and mineral
species, he, like other chemists, was driven to construct chemical for-
mulas much more complex than those which satisfied the requirements
of the Daltonian atomic theory as it had been previously understood.

This New Basis of Chemistry was to Hunt no longer theory, but
fact. He had believed for many years that the solid and liquid min-
eral species known to us are formed by processes of intrinsic condensa-
tion, or so called polymerization, from simple chemical species. He

372 JOSEPH LOVERING.

kuew, with every chemist, that the determination of the coefficient of
condensation is a problem of the highest moment, — a problem which
had been neglected in the belief that it did not admit of solution.
When, therefore, in 1886, he reached what he regarded as a solution
of this insoluble problem, and propounded the theorem that "the
volume, not only of gases and vapors, but of all species, whether
gaseous, liquid, or solid, is constant, and that the integral weight
varies directly as the density," he rejoiced in the conviction that he
had realized and expressed one of the great laws of nature, after which
he had been groping all his life.

While throughout all his maturer years he pondered over the deeper
problems of pure science, he was also actively engaged in practical pur-
suits. The papers he has written on technical subjects would fill well-
nigh as many volumes as his theoretical and purely scientific memoirs.

It is proper to state that this notice has been, in the main, compiled
from those which have appeared elsewhere, and especially from the
extended biographical sketch read by Mr. James Douglas before the
American Institute of Mining Engineers last June, and published in
the current volume (XX.) of the Transactions of the Institute.

JOSEPH LOVERING.

Professor Lovering was born to humble circumstances at
Charlestown, Massachusetts, December 25, 1813, and received his
early education in the public schools of that place. His father,
a subordinate town officer, was a member of the Harvard Church,
then under the pastoral care of the Rev. Dr. James Walker, sub-
sequently Professor in Harvard College and its President. At the
public school, young Lovering had proved himself an apt and
bright scholar, and this circumstance led to his employment by
Dr. Walker as a reader. The prophetic judgment of this wise man,
whom Harvard students so soon after learned to respect and honor,
recognized in the lad unusual promise, and he not only encour-
aged him to prepare for college, but also aided him with personal
instruction and advanced the money necessary to pay his college
expenses, a loan which he was soon able to repay. In 1830 Lov-
ering entered the Sophomore Class at Harvard, and was graduated
in due course in 1833. He was a distinguished scholar, standing
fourth in a class which furnished six Professors to the Alma Mater
and four to other institutions. At the Commencement he de-
livered the Latin Salutatory Oration, and three years later, when

JOSEPH LOVERING. 373

his class were entitled to receive the Master's degree, he delivered
the Valedictory Oration, according to the custom of that day.

Duriug the first year after his graduation, Mr. Lovering taught
a small private school in Charlestown. In the autumn of 1834 he
entered the Divinity School in Cambridge, and remained there two
years. During a part of the academical year 1834-35 he assisted
Professor Peirce in the instruction of the College classes in mathe-
matics. In 1835-36 he was Proctor aud Instructor in mathemat-
ics, and during a part of the year he conducted the morning and
evening services in the College Chapel in place of the regularly
officiating clergyman. In 1836-37 he was Tutor in Mathematics
aud Lecturer in Natural Philosophy, taking the work of Profes-
sor Farrar, whose failing health had led him to resign, and in 1838
he definitely succeeded Professor Farrar as Hollis Professor of
Mathematics and Natural Philosophy. The active duties of this
office Professor Lovering discharged without assistance for the un-
precedented term of fifty years and on resigning in 1888 he was
appointed by the Corporation of the University Hollis Professor
Emeritus, and thus continued his connection with the institution
until his death, — in all, from 1834 to 1892, a period of fifty-eight
years, thus exceeding by three years the term of Tutor Flynt (1699-
1754), hitherto regarded as the College Nestor.

It must have been a severe ordeal to a young man to succeed
such a brilliant lecturer as Professor Farrar ; but the event showed
that, although a lecturer of a very different type, Professor Lover-
insfs instruction was no less effective than that of his celebrated
and popular predecessor. Professor Lovering delivered nine courses
of twelve lectures each before the Lowell Institute, and the first
four of these, given at the Odeon on Federal Street between
1840 and 1844, the writer attended, and remembers distinctly how
instructive and popular they were. Professor Lovering had great
clearness of thought and singular definiteness and felicity of ex-
pression. He was apt in illustration, and a quiet humor often en-
livened what would have been otherwise a dry demonstration. He
gave most careful attention to the mechanical preparation of his
lectures, and his experiments rarely failed of success. Besides his
regular college lectures, during term time always one and usu-
ally two a week for a long period of years, and the lectures at
the Lowell Institute above referred to, Professor Lovering gave
shorter courses at the Smithsonian Institution in Washington, the
Peabodv Institute of Baltimore, and the Charitable Mechanics'

37-1 JOSEPH LOVERING.

Institution of Boston, and one or more lectures in many towns
and cities of New England.

The wonderful clearness and elegance of exposition so conspicu-
ous in Professor Lovering's lectures appeared also in his mono-
graphs and popular essays on scientific subjects. These are very
numerous, and are models of scientific style. They are scattered
through various serial publications, and are probably known to but
few of the present generation ; but they represent his very best
work, and in justice to his memory they ought to be collected and
reprinted. Besides their intrinsic value as the literary work of a
very successful teacher, they are valuable material for the history of
science. Professor Lovering's long career covers a period of won-
derful development in all departments of physics, not simply in
the discovery of new facts, but also in the change of aspect under
which the old facts are regarded. Our late colleague was a broad
scholar, not only familiar with the past history of every branch of
his subject, but also accustomed to look at facts from all sides. If
a student who had fallen into the rut of a system went to him
with a difficulty, — perhaps insuperable on that theory, — he would
surmount the difficulty by taking the man out of the rut, and thus
enabling him to look at the facts from a different point of view.
How different would be our judgment of the alternating phases
in the past history of science, — of the labors of the alchemists, for
example, — if we could only see the facts as our fathers necessarily
regarded them ; and the most striking feature of Professor Lovering's
essays is the circumstance that the point of view from which lie
writes is made so clear. Moreover, a comparison of the earlier
essays with the later shows how the point of view changed, and
that the author, acute scholar as he was, had closely followed the
change.

The following contemporary notices fully justify the writer's
estimate of these occasional essays, which are enumerated in the
catalogue of his publications at the end of this notice. A scholar
of high scientific eminence has recently written of these essays,
that they impressed him as few others had ever done. "It will
surprise him to know it ; yet it is true that the ideas then pre-
sented, and with an elegance worthy of their breadth and power,
affected the whole tenor and tendency of my thoughts, and thus of
my subsequent life." And he compares the style of parts of them
with that of the most classic passages in Babbage's Ninth Bridge-
water Treatise.

JOSEPH LOVERING. 375

So also Mr. R. W. Emerson published the following notice in " The
Dial " : •' We rejoice in the appearance of the first number of this
quarterly journal edited by Professor Peirce. Iuto its mathemat-
ics we have not ventured ; but the chapters on Astronomy and
Physics we read with great advantage and refreshment. Espe-
cially we thank Professor Lovering for the beautiful essay on the
' Internal Equilibrium and Motion of Bodies,' which is the most
agreeable contribution to scientific literature which has fallen under
our eye since Sir Charles Bell's work on the hand, and brings to
mind the clear, transparent writings of Davy and Playfair."

Professor Lovering was not a writer of books, but he was an
editor of very large experience. He was co-editor with our late
colleague, Professor Benjamin Peirce, of the " Cambridge Miscel-
lany of Mathematics, Physics, aud Astronomy," published at Cam-
bridge in 1842 and 1843, and devoted to pure and applied math-
ematics. He edited fifteen volumes of the Proceedings of the
American Association for the Advancement of Science, also six
volumes of the Memoirs and three volumes of the Proceedings of
this Academy, and earlier, in 1842, a new edition of Farrar's
Electricity and Magnetism. In 1873 he was the President for the
year of the American Association, and in his reception address at
Portland he said : " Few of us can aspire to the honor of being
discoverers of the laws of nature in the highest sense of that
phrase. But no one, however humble his capacities, or however
limited his opportunities, who labors for science, will fail to ad-
vance it." This well expresses the attitude of our colleague towards
his profession. He was not a born investigator, but one whose
patli in life was determined by force of circumstances, rather than
by natural predilections. He was primarily a scholar, and the great
service which he rendered to science was that of a scholar and a
teacher, and not that of an experimenter. At the present day.
courses of research in all departments of study are the latest fad
at many of our higher institutions of learning ; but excepting al-
ways the few highly favored men of the race to whom an unusual
scientific insight has been given, it may be a question whether the
broad scholar does not exert a greater influence on the advancement
of knowledge than the average specialist.

But although Professor Lovering seems to have had little inclina-
tion to undertake original experimental investigation in Physics, he
did a very large amount of work in observing and correlating facts.
He was associated with the late Professor William C. Bond in the

370 JOSEPH LOVERING.

management of the primitive astronomical observatory first located
at Cambridge in the dwelling-house still remaining on the corner of
Quincy and Harvard Streets, and there took part in that concerted on-
set on the problem of the earth's magnetism instituted by Humboldt
and Gauss, and continued throughout the British Empire for several
years under the direction of the Royal Society of London. An appeal
was made to various academies and men of science in this country to
co-operate in the work, and the appeal was responded to by the Mag-
netic Observatory at Philadelphia under the care of the late Professor
Bache, and by the Americau Academy of Arts and Sciences in Boston,
who supplied the Cambridge Observatory with the requisite instru-
ments. The plan of the Royal Society involved, besides frequent reg-
ular daily observations, an almost continuous watch on the magnetic
needle during one day of each mouth. On these days, called term
days, observations were made every five minutes on three different
instruments, day and night. The chief burden of all this work fidl
on Professor Lovering, although he was greatly assisted, not only
in the observations themselves, but also in their reduction and in
the mathematical discussion of the results, by Professors Bond and
Peirce and a few competent undergraduates. Of these last, the late
Thomas Hill, afterward President of Harvard College, and Benja-
min A. Gould, the present distinguished astronomer, deserve special
mention.

Professor Lovering's experience in this famous magnetic campaign
must have familiarized him with the magnetic disturbances accompany-
ing the auroral discharge, and thus led him to discuss the mooted ques-
tion of the periodicity of the aurora. His study of this problem was
the most considerable work of his life. It involved the collating and
discussing of an immense number of more or less indefinite observa-
tions, and the mere presentation of the result of this long and laborious
investigation occupies over 350 pages of the quarto Memoirs of this
Academy, New Series, Vol. X. Part I. In this memoir, Professor
Lovering clearly defined the secular periods of the aurora, and also
showed that no apparent connection could be traced between the
secular periodicity of the aurora and the secular changes of the earth's
magnetism, the periods of sun-spots, fire-balls, or earthquakes, or any
other secular changes with which the aurora had been associated
by various physicists. As he writes in this memoir, " A lesson of
caution against hasty conclusions on subjects of such complexity may
be drawn from the fact, that whereas Bone favored the conclusion
that the aurora goes hand in hand with the earthquake, and whereas

JOSEPH LOVERING. 877

Wolf had decided, though from data afterwards acknowledged to be
insufficient, that years rich in sun-spots corresponded to years rich in
earthquakes, Kluge, from a more searching examination and the use
of larger materials, finds a periodicity for earthquakes as long as
that which governs the sun-spots and magnetic disturbances, but with
maxima and minima reversed." We quote this as an indication of
our colleague's judgment and caution in the discussion of observations,
and although the investigation did not lead to the discovery of unsus-
pected relations, yet the negative results reached were of the greatest
importance, and the memoir just quoted may be referred to in our
transactions with pride, as an example of great thoroughness in
the collection of materials, and of remarkable freedom from bias in
the discussion of results.

Between 1867 and 1876 Professor Lovering was connected with the
United States Coast Survey, and had charge of the computations for
determining differences of longitude in the United States, and across
the Atlantic Ocean, by means of the land and cable lines of telegraph.
The most important and interesting portion of the work which he did
in this connection is discussed in a paper " On the Determination of
Transatlantic Longitudes by Means of the Telegraphic Cables com-
municated to the Academy, January 29th, 1873," by permission of the
Superintendent of the Survey, and published in the Memoirs, New
Series, Vol. IX. page 437.

As might be expected from the character and direction of his
scientific work, Professor Lovering had marked executive ability, and
in all such relations he was in the highest degree methodical, accurate,
and just. During 1853-54 and from 1857 till 1870 he was Regent,
then the second executive officer of Harvard College. During this
period he kept with his own hands such full and accurate accounts of
the merits and demerits of each undergraduate that the Faculty could
make his reports the basis of action with entire confidence, while at
the same time in dealing with the students he showed such just dis-
crimination and kindly appreciation that he gained their universal
confidence and esteem.

When the Jefferson Physical Laboratory was opened, in 1884,
Professor Lovering was appointed its " Director," and during the four
years of his administration made " Annual Reports " of its activities.
To this laboratory he carried the very large and valuable collection of
philosophical apparatus which he had gradually accumulated during
his long period of service as Hollis Professor. Mr. Lovering took
great pleasure and a just pride in this collection. When he entered

378 JOSEPH LOVERING.

upon his office, there was already in the possession of his department a
no inconsiderable number of philosophical instruments, some of which
had a real historical interest, but they did not meet the requirements of
a more modern science. Only a small annual appropriation could be
obtained for the expenses of his lectures ; but by carefully husband-
ing the resources, and doing all the mechanical work with his own
hands, he was able from time to time not only to purchase the indis-
pensable articles, but also to procure all the novelties as they appeared.
He judiciously used his large knowledge and judgment in the original
selection, and by constant watchfulness prevented the apparatus from
deteriorating, and thus during his long term of service he brought
together one of the most complete cabinets of physical apparatus in
this country. Nothing delighted him more than some new mode of
illustrating a recondite principle in a striking way, and every year, at
the meeting of the old Scientific Club of Cambridge he would delight
his associates also by bringing forward and explaining some such piece
of apparatus, and he rose to the highest point of enthusiasm when he
made it to appear that the paradoxes of science were no paradoxes at
all, but the necessary unfoldings of fundamental laws.

Besides his uninterrupted work for the College, Professor Lovering
discharged other executive duties in which he exhibited his usual faith-
fulness and good judgment. From 1854 to 1873 he was the Perma-
nent Secretary of the American Association for the Advancement of
Science, — an office which requires an unusual amount of executive
skill, besides tact and affability. On the Permanent Secretary de-
volve the arrangements for the annual meeting, the collection and dis-
bursement of the funds, and the publication of the yearly volume of
Proceedings. It is all important that he should commend the Asso-
ciation to the successive communities where it meets, and commend
himself to the local committees. All this service Professor Lovering
rendered with great success, and carried the society through the dis-
integrating period of the Civil War, when its continued life seemed
impossible, and so skilfully managed its finances as not only to print
a volume of Proceedings every year, but also to leave in the treasury
at the end of his term of office a valuable stock of publications and
a goodly cash balance. On resigning this office, Mr. Lovering was
elected President of the Association, and served as such at the Port-
land meeting of 1873. Both his reception and his retiring addresses
were admirable in thought as well as in spirit, and are excellent
examples of the best use of idealism in science.

In the first of these he said : " It is impossible for the man of

JOSEPH LOVERING. 379

science to serve two masters, the Kingdom of Nature and Mammon.
It is a dangerous thing for him to be thinking of the utility of his dis-
coveries, or of the pecuniary profit which may be made out of them."
And in the second he adds : " Science is not destructive, but pro-
gressive ; while its theories change, the facts remain. Its general-
izations are widening and deepening from age to age. We may
extend to all the theories of physical science the remark of Grote
which Challis quotes in favor of his own : ' Its fruitfuluess is its cor-
rectibility.' Instead of being disheartened by difficulties, the true
man of science will congratulate himself, in the words of Vauve-
nargues, that he lives in a world fertile in obstacles. Immortality
would be no boon if there were not something left to discover, as
well as to love."

Professor Loveriug was also for some years one of the trustees of
the Tyndall Fund for the endowment of research in physics, and
during the last few years of his life he was one of the Trustees of
the Peabody Museum of American Archaeology and Ethnology.

Professor Lovering was long and intimately associated with our
Academy. He was elected Fellow on January 30, 1839, and the only
surviving member on our list whose election antedates his is our
honored colleague, Dr. O. W. Holmes. From 1851 to 1872 he was
a member of the Committee of Publication. From 1847 to 1868,
and again from 1878 to his death, he was a member of the Rumford
Committee, and during the greater portions of these periods its chair-
man, directing its deliberations and inspiring a proper caution in the
expenditure of the funds as well as in the bestowal of the medals
under its charge. From 1852 to 1863, and again from 1865 to 1868,
he held a place on the Council of the Academy by annual election,
and during the rest of his life ex officio. From 1869 to 1873 he
was Corresponding Secretary. From 1873 to 1880 he was Vice-
President, and from 1880 to his death President. Thus our late col-
league's membership has covered fifty-three of the one hundred and
twelve years which have passed since the Academy was incorporated,
under the Presidency of Governor James Bowdoin, in 1780. During
this long period, nearly one half of its whole history, Professor Lov-
ering through his force of character and commanding knowledge
exerted a controlling influence in its affairs. For many years he
superintended its publication, and the prosperity of our society during
the second half-century of its life was in no small measure due to his
fostering care. Mr. Lovering Was also a member of the National
Academy of Sciences, of the American Philosophical Society of

380 JOSEPH LOVERING.

Philadelphia, of the California Academy of Sciences and of the Buffalo
Historical Society. In 1879 he received from his Alma Mater the
degree of Doctor of Laws.

Professor Lovering was pre-eminently a social man, and any notice
of him would he incomplete that did not allude to this genial phase
of his character. He was one of the few men who could hold his
opinions and maintain his position without personal animosity or
unfriendly feeling, could favor without partisanship, could oppose
without bitterness. He never would quarrel, and, as he once said to
the writer, it takes two to make a quarrel and the other man only
counts one. Besides a frank cordiality and kindliness of greeting
which made him very accessible, he had a fund of dry humor, which
not only enlivened intercourse, but often gave force to an argument.
Not unfrequently in meetings of the College Faculty he would turn
a stupid debate, and exhibit a question in its real absurdity, by a
witty remark. There was also a straightforwardness, integrity, and
truthfulness about his intercourse which inspired confidence and
warmly attached him to his friends. He was perfectly just and
singularly free from bias, and in any question involving rectitude
or faithfulness you could always count on him. He was faithful to
every duty, and conscientiously discharged every obligation. He
rarely, if ever, missed an appointment, and whatever he undertook,
however unimportant, he did with all his might.

Besides attending and keeping up the spirit of the Cambridge
Scientific Club above referred to, of which he was one of the original
members, he was uniformly present at the meetings of the Thursday
Evening Club in Boston, and often contributed to its proceedings.
He very greatly enjoyed those meetings, and his communications
were always esteemed by the members. He had the happy faculty
of popularizing a subject without degrading it. He could present a
problem so that his audience could follow as far as he led, and under-
stand why he did not attempt to lead them further. His discourse
was always free from trivialities or redundances, and his hearers could
appreciate the grandeur of the mountain all the better because they
had not made a fruitless attempt to climb it.

It was a very fitting tribute to Professor Lovering's warm social
nature, that at the close of his active duties, in 1888, a banquet
should be held in honor of his fifty years' service. It was the spon-
taneous offering of classmates, associates, pupils, and friends, and it
afforded him the highest satisfaction. Besides the social pleasures
and warm eulogiums of the time, the occasion led to two enduring

JOSEPH LOVERING. 381

memorials ; first, a silver teapot, (copied from one formerly used by
Tutor Flynt, now in the possession of Dr. O. W. Holmes,) which
will be handed down as an heirloom in his family ; and, secondly, a
portrait painted by Linden Smith, which will hold his likeness on the
walls of Memorial Hall.

Professor Lovering was married in 1844 to Sarah Gray Hawes
of Boston, and his wife, with two sons and two daughters, survive
him. Since retiring from active work, he has passed four serene and
happy years. He several times said to the writer, " You don't know
what a pleasure it is to be relieved from stated duties, and to have
full command of your time. I have plenty to do, and never have an
idle moment." Through great prudence and thrift he had laid aside
a sufficient competency to relieve him from all pecuniary anxieties
and his friends had hoped that he might long pass the full term
of fourscore years. His wonderful vitality and singular immunity
from disease encouraged this hope. He said to his classmate, Dr.
Morrill Wyman, who had been his family physician for half a century,
and who was feeling his pulse during his last illness, " No one has
felt my pulse before since I was a child." But it was not to be.
A severe cold complicated by the prevailing epidemic attacked the
heart, and the end came in the early morning of January 18, 1892.
The change was peaceful, and without pain.

The following catalogue of Professor Lovering's publications is
taken from the College Class-book entitled "Memorials of the Class
of 1833 of Harvard College, prepared for the Fiftieth Anniversary
of their Graduation by the Class Secretary, Waldo Higginson " ;
and preceding the catalogue the Secretary states that it was fur-
nished by Professor Lovering. The present writer has only added
a few items of papers which to his knowledge have appeared
since.

1. An Account of the Magnetic Observations made at the Magnetic

Observatory of Harvard College. In Two Parts. (Memoirs of the
American Academy, vol. ii., 1846.)

2. On the Secular Periodicity of the Aurora Borealis. (Ibid., vol.

ix.)

3. On the Determination of Transatlantic Longitudes by Means of the

Telegraphic Cables. (Ibid., 18G7.)

4. Catalogue of Auroras observed, mostly at Cambridge, after 1838.

(Ibid., vol. x., 1868.)

5. On the Periodicity of the Aurora Borealis. In Two Parts. (Ibid.,

with plates, 1868.)

382 JOSEPH LOVEUING.

6. On the Causes of the Difference in the Strength of Ordinary Magnets
and Electro-magnets, of the same Size and Shape. (Proceedings
of the American Academy, vol. ii.)

7 On the Law of Continuity. (Ibid.)

8. On the Aneroid Barometer. (Ibid.)

9. Electrical Experiment. (Ibid., vol. iv.)

10. On the Connection of Electricity with Tornadoes. (Ibid., vol. ii.)

11. On Corona? and Halos. (Ibid.)

12. On the Spectroscope. (Ibid., vol. lii.)
13 On the Bioscope. (Ibid.)

14. Apparatus for Rapid Rotations. (Ibid.)

15. Shape of Luminous Spots in Solar Eclipses. (Tbid.)

16. Notice of the Death of John Farrar. (Ibid.)
17 Notice of the Death of Melloni. (Ibid.)

18. New Apparatus and Experiments in Optics and Acoustics. (Ibid.)

19. Arago's Opinion of Table-Moving. (Ibid.)

20. On Fessel's Gyroscope. (Ibid.)

21. Apparatus to regulate the Electric Light. (Ibid.)
22 Does the Mississippi River flow Up-hill? (Ibid.)

23. Report on Hedgcock's Quadrant. (Ibid )

24. On the Boomerang. (Ibid., vol. iv.)

25. Report on Meteorological Observations. (Ibid.)

26. On the Ocean Cable. (Ibid.)

27. On the Polarization of the Light of Comets. (Ibid.)

28. Report on the Polar Expedition of Dr. I. I. Hayes. (Ibid.)

29. On Records of the Aurora Borealis. (Ibid )

30. First Observations on the Aurora in New England. (Ibid.)

31. Notice of the Death of Biot. (Ibid., vol. ii.)

32. On the Velocity of Light and the Sun's Distance. (Tbid.)

33. Notice of the Death of O. M. Mitchell. (Ibid.)

34. On the Optical Method of studying Sound. (Ibid., vol. vii.)

35. On the Periodicity of the Aurora Borealis. (Ibid., vol. viii , 1873.)
30. On the French Republican Calendar. (Ibid.)

37. Application of Electricity to the Motion of Tuning-Forks. (Ibid.)

38 On Optical Meteorology. (Ibid.)

30. On Transatlantic Longitudes. (Ibid.)

40. Notice of the Death of William Mitchell. (Ibid.)

41. Notice of the Death of Faradav. (Ibid.)

42. Notice of the Death of David Brewster. (Ibid.)

43. Notice of the Death of J. W. F. Herschel. (Ibid.)

44. Notice of the Death of Christopher Hansteen. (Ibid , vol. ix.)

45. Notice of the Death of Auguste A. de la Rive. (Ibid.)

46. Notice of the Death of James Walker. (Ibid., vol. x.)
47 Notice of the Death of Joseph Winlock. (Ibid., vol. xi.)
48. Notice of the Death of Alexis Caswell. (Ibid., vol. xii.)

JOSEPH LOVERLNG. 383

40. Notice of the Death of John II Temple. (Ibid., vol. xiii.)

50. Notice of the Death of Joseph Henry. (Ibid., vol. xiv.)

51. Notice of the Death of H. W. Dove. (Ibid., vol. xv.)

52. Address as President on presenting the Rumford Medal to J. Willard

Gibbs. (Ibid., vol. xvi.)

53. Anticipations of the Lissajous Curves. (Ibid.)

54. Notices of the Deaths of Richard H. Dana, of Edward Desor, and of

John W. Draper. (Ibid., vol. xvii.)

55. Notice of the Death of Sir Edward Sabine. (Ibid., vol. xix.)

56. Address of the President on presenting the Rumford Medal to H. A.

Rowland. (Ibid.)

57. Address as President on presenting the Rumford Medal to S. P.

Langley. (Ibid., vol. xxii.)
5S\ Notice of the Death of Gustav Robert Kirchhoff . (Ibid., vol . xxiii )
5Sb. Address as President on presenting the Rumford Medal to A. A.

Michelson. (Ibid., vol. xxiv.)
58°. The " Mecanique Celeste" of Laplace, and its Translation by Bow-
ditch. (Ibid., vol. xxiv.)

59. On the Electro-dynamic Forces. (Proceedings of the American Asso-

ciation for the Advancement of Science, vol. ii.)

60. On a Curious Phenomenon relating to Vision. (Ibid.)

61. On a Singular Case of Interference in the Eye itself. (Ibid., vol. vii.)

62. On a Modification of Soleil's Polarizing Apparatus. (Ibid.)

63. On the Australian Weapon called the Boomerang. (Ibid., vol. xii.)

64. On the Optical Method of studying Sound. (Ibid., vol. xvi., 1868.)

65. On the Periodicity of the Aurora Borealis. (Ibid.)

66. Sympathetic Vibrations between Tuning- Forks and Stretched Cords.

(Ibid.)

67. On Methods of illustrating Optical Meteorology. (Ibid., vol. xix.,

1871.)

68. On Sympathetic Vibrations. (Ibid., vol. xxi., and Journal of the

Franklin Institute, May, 1873.)

69. Addresses as President at the Portland Meeting of the American

Association for the Advancement of Science. (Proceedings of
the A. A. A. S., vol. xxiii.)

70. On a New Way of illustrating the Vibrations of Air in Organ-Pipes.

(Ibid.)

71. Address as Retiring President. (Ibid. ; republished in the Popular

Science Monthly, American Journal of Science, and the Loudon
Philosophical Magazine.)

72. On a New Method of measuring the Velocity of Electricity. (Pro-

ceedings of the American Association for the Advancement of
Science, vol. xxiv. ; also Journal de Physique, tome vi.)
7:5. Shooting Stars (American Journal of Science, vol. xxxv.)
74. The American Prime Meridian. (Ibid., N. S., vol. ix., 1850.)

884 JOSEPH LOVER1NG.

75. The Aneroid Barometer. (Ibid.)

76. On the Velocity of Light and the Sun's Distance. (Ibid., N. S., vol.

xxxvi.)

77. Melloni's Researches on Radiant Heat. (American Almanac, 1850.)

78. Animal Electricity. (Ibid., 1851.)

79. Recent Discoveries in Astronomy. (Ibid., 1852.)

80. Comets. (Ibid., 1853.)

81. Atmospherical Electricity. (Ibid., 1854 and 1855.)

82. Lightning and Lightning-Rods. (Ibid., 1856.)

83. Terrestrial Magnetism. (Ibid., 1857.)

84. Theories of Terrestrial Magnetism. (Ibid., 1859.)

85. On the Boomerang. (Ibid., 1859.)

86. On the Aurora Borealis and Australis. (Ibid., 1860.)

87. On Meteorology. (Ibid., 1861.)

88. On the Pressure of the Atmosphere and the Barometer. (Ibid., 1862.)

REVIEWS, etc.

89. Guyot's Physical Geography. (Christian Examiner, vol. xlvii.)

90. Humboldt's Cosmos. (Ibid., vol. xlviii.)

91. Scepticism in Science. (Ibid., vol. li.)

92. Spiritual Mechanics. (Ibid., vol. lv.)

93. Thompson and Kaemtz on Meteorology. (North American Review,

vol. lxxi.)

94. Elementary Works on Physical Science. (Ibid., vol. lxxii.)

95. Michael Faraday. (Old and New, vol. i.)

96. Reports on Lighthouses. By Benjamin Peirce and Joseph Lovering-

(Journal of the Franklin Institute, vol. xviii.)

97. On the Internal Equilibrium and Motion of Bodies. (Cambridge

Mathematical Miscellany, vol. i.)
9S. On the Application of Mathematical Analysis to Researches in the

Physical Sciences. (Ibid )
99.' Encke's Comet. (Ibid.)

100. The Divisibility of Matter. (Ibid.)

101. Boston and Science. (Memorial History of Boston, vol. iv.)

102. Article on the Telegraph. (American Cyclopaedia, last edition.)

103. Address at the Dedication of the Mural Monument to the Memory

of Dr. James Walker, in the Harvard Church, Charlestown.

104. Notice of the Death of F. A. P. Barnard. (Proceedings of the

American Academy, vol. xxiv.)

SUBJECTS OF LECTURES AT THE LOWELL INSTITUTE.

1840-41. Electricity and Magnetism.
1841-42. Mechanics.
1842-43. Astronomy.

GEORGE UINCKLEY LYMAN. 385

1843-44. Optics.

1845-46. Astronomy.

1853-54. Electricity and Magnetism.

1S59-60. Astronomy.

1865-66. Light and Sound.

1S79-80. Connection of the Physical Sciences.

GEORGE HINCKLEY LYMAN.

Dr. George Hinckley Lyman, Resident Fellow of the Academy,
was born in Northampton, Mass., July 17, 1819, the son of Jonathan
Huntington and Sophia (Hinckley) Lyman. He was educated at
the famous Round Hill School iu Northampton ; but on account of ill
health he was obliged to pass several years in Ohio and other Western
States before beginning his professional studies in the University of
Pennsylvania, at Philadelphia, where he took his degree of M. D.
in 1843. Wishing to qualify himself thoroughly for the practice of
his profession, he devoted more than the usual time to advanced study
and clinical observation in the great hospitals of Europe, before return-
ing to establish himself in Boston. Here he at once attracted attention
through the publication of two Essays, — on " Non-Malignant Diseases
of the Uterus," and on the " History and Statistics of Ovariotomy," —
which had gained prizes offered by Medical Societies as being valuable
contributions to the knowledge of the profession, and marked by the
wise discrimination and candor shown in the discussion of their sub-
jects, to which was added the charm of clearness and elegance of style.

The early promise thus given of Dr. Lyman's career was amply
fulfilled. His thorough training, quickness of observation, and good
judgment, with his faithful ministrations and ready sympathy, invited
and retained the confidence of his patients of high or low degree.

But his success as a physician did not make him heedless of the
claims of his country. At the outbreak of the Civil War, in 1861, he
volunteered his services to Governor Andrew of Massachusetts, and,
in co-operation with Surgeon General Dale, become his efficient ad-
viser in the organization of a suitable surgical and ambulance service
for the departing troops. Nor did he linger in the rear. As these
went to the front, he went to share their dangers and alleviate their
sufferings.

Standing first on the list of candidates examined by the Medical
Army Board of Washington, he outranked during the war all the ap-
pointees from civil life. He was soon assigned as Medical Director of
vol. xxvu. (n. s. xix.). 25

386 GEORGE HINCKLEY LYMAN.

the Division commanded by General Fitz John Porter, and afterward
of the entire Fifth Corps, comprising twenty-six thousand men. Pros-
trated for a time by the severe fatigues and exposures ensuing after
the exhausting marches and sanguinary battles at Gaines's Mill and
elsewhere, Dr. Lyman was upon his recovery appointed one of six
Medical Inspectors of the Army, with the rank of Lieutenant Colonel ;
and ordered to inspect the great hospitals at Baltimore, Washington,
Philadelphia, and New York. Next he was given supervision of the
Medical Department which included Kentucky, Tennessee, West Vir-
ginia, and Ohio, and as far southward as our army lines extended;
finding in Nashville and some other large cities the churches, ware-
houses and many dwellings overflowing with the wounded. Afterwards
he travelled more than three thousand miles by rail through the Depart-
ment of the East, to investigate alleged hospital abuses ; and was then
transferred to the Department of the South, to inspect the hospitals,
and to await the arrival of Sherman's army on its march to the sea,
and report on its sanitary condition.

In the important positions he held on the Army surgical staff,
Dr. Lyman worked indefatigably to organize and to improve the
supply, ambulance, and hospital services.

At the close of the war, Dr. Lyman by no means reposed on his
laurels, but returned with fresh zeal to his home life and professional
work. In addition to his private practice, he filled until his decease
the post of Visiting Physician to the Boston City Hospital, where his
wide experience, his devotion to the patients under his charge, and his
courteous relations with his colleagues of the staff, caused his loss to be
deeply felt.

In 1875 Dr. Lyman delivered the Annual Oration before the Massa-
chusetts Medical Society, on " The Interests of the Public and of the
Medical Profession"; in 1870 he was its Anniversary Chairman; and
in 1879-80 he received the highest honors in the gift of the profession,
in his election for the two years as President of the Society, where
his administrative talent, and his tact, dignity, and courtesy as a pre-
siding officer did much to promote its interests.

Dr. Lyman was one of the founders and officers of the Massachusetts
Medical Benevolent Society, instituted to aid such worthy members of
the profession, or their families, as had through illness or misfortune
fallen into distress. He was also one of the founders of the American
Gynecological Society, and an active member of the Boston Obstetrical
Society, of the Boston Society for Medical Improvement, of the Mili-
tary Historical Society of Massachusetts, and of the Military Order

GEORGE HINCKLEY LYMAN. 387

of the Loyal Legion of the United States. He was an Honorary
Member of the Harvard Medical School Association, and for many
years was vestryman of St. Paul's Church.

In the various societies for medical improvement of which Dr.
Lyman was an honored, an active, and an interested member, his
qualities as an original thinker and accurate observer, and his large ex-
perience, to which was added much aptness and conciseness in debate,
gave weight to every expression of his opinions.

In his visits abroad during nearly a half-century of professional life
Dr. Lyman had made the acquaintance of many medical and scientific
men of celebrity ; and he delighted in extending to some of these, vis-
iting this country, his graceful welcome and hospitalities, to which his
own cultivated taste in matters of literature and art gave additional
charm.

Dr. Lyman was in no respect a passive man. Of active temperament,
quick and independent in thought and deed, earnest in convictions,
unchanging in friendships, with a high sense of honor, he was always
ready to promote a good work, but impatient of wilful negligence or
imposture. His busy career compelled him to limit his attention to
matters more or less germane to his profession, rather than to under-
take elaborate and minute scientific researches ; but he solaced the
intervals of a laborious professional life with literary enjoyments and
when at times he contributed something for publication it was notable
for clearness and elegance of diction, and bore the stamp of trust-
worthiness.

Dr. Lyman married, first, October 14, 1846, Maria Cornelia Ritchie,
daughter of James T. Austin ; she died in 1864, leaving two sons and
two daughters. He married, second, February 13, 1879, Henrietta,
daughter of Samuel T. Dana, who survives him.

Having gone abroad in the spring of 1890, Dr. and Mrs. Lyman
passed the ensuing winter in Italy, and the summer in Switzerland
and Paris. On reaching London in August, Dr. Lyman had an attack
of facial erysipelas, from which he had four times previously suffered,
and which ten years previously had been complicated with a deep-
seated orbital abscess causing loss of vision in one eye. The same
conditions now recurred, and were combined with embolism of the
femoral artery. He early became unconscious, and died on the 19th
of August, 1891. His interment took place at Mount Auburn, on
the 2d of September.

388 DAVID HUMPHREYS STORER.

DAVID HUMPHREYS STORER.

David Humphreys Storer was born in Portland, Me., March 26,
1804, and died in Boston, September 10, 1891. His father was Chief
Justice of the Court of Common Pleas at Portland, and an elder brother
became Chief Justice of the Supreme Bench of Ohio. Through his
father he was descended from Governor Langdon of New Hampshire,
one of the signers of the Declaration of Independence, and through
his mother from Governor Dudley of the Massachusetts Bay Colony.
Dr. Storer graduated at Bowdoin College in 1822, studied medicine
in Boston under Dr. John C. Warren, and took his degree at the Har-
vard Medical School in 1825. He at once entered upon the practice
of his profession in Boston, and after the hard struggle to which even
talent is exposed in a strange city he gained position as one of the
leading practitioners of Boston. In 1837, with Dr. Jacob Bigelow
and others, he established the Tremont Street Medical School, a pri-
vate school " which, as the germ of the present curriculum of Harvard,
has borne much valuable fruit," but afterwards, in 1854, took the
Chair of Obstetrics and Medical Jurisprudence in the Harvard Medical
School, where he became Dean, in which capacity he served for many
years.

His great success in the medical field has been properly recorded by
his colleagues, and need not be further noticed here, since it was for
his work in another department that he was chosen to the Zoological
Section of the Academy, November 8, 1837.

Like most naturalists who have distinguished themselves in later
life, his interest in natural history began at an early period. Entering
college when not yet fourteen years of age, he came under the influ-
ence of Prof. A. S. Packard, for whom he retained through life a
warm affection and admiration. At first mineralogy particularly in-
terested him, and he greatly enjoyed the field excursions to mineral
localities made with Professor Packard ; the collections then made
were afterwards given to one of his sons, and put to good service in
teaching the first classes in the Institute of Technology.

Yet his taste for natural history at that early period was by no
means confined to minerals ; entomology engaged much of his atten-
tion, and he gave popular lectures on insects in the days when lyceum
lectures were first instituted ; he was also devoted to ornithology, and
made at one time a large collection of birds' eggs ; indeed, it was
through his example and interest that his brother in law, our late
associate, Dr. T. M. Brewer, became a student in this field. His taste

DAVID HUMPHREYS STORER. 389

for collecting extended even to coins. At one time he was in league
with all the toll gatherers on the Boston bridges, and they kept for
him any odd pieces of money which fell into their hands. This pas-
sion for numismatics, it may be added, appears to have been handed
down to his desceudants, one son being still deeply interested in the
subject, and a grandson the Curator of the Coins belonging to Harvard
University. The coin-collecting mingled curiously with his Natural
History interests, and we are told that he persuaded the keepers of
several sailor's boarding-houses to secure for him any coins, shells,
or fishes which their guests might have obtained in foreign parts.

It was natural that he should join the Boston Society of Natural His-
tory, which he did immediately after its foundation in 1830, so that he has
always been enrolled as one of the " original members," though he was
not strictly such ; his activity is attested to by his being chosen a few
months later Recording Secretary, a post he held for nearly six years.
At this time he appears to have been giving special attention to Mol-
lusca, and as a number of other gentlemen at the same period in our
city were also forming collections, it was doubtless from the enthu-
siasm born of this common interest that he ventured to issue the pros-
pectus of a contemplated translation of Kiener's " Iconographie," then
in course of publication in Paris ; but for lack of support only one part
of the translation ever appeared, an octavo of about a hundred and
fifty pages, issued in 1837. His own collection, kept until his death,
has recently been given to Bowdoin College.

It is apparent, then, that in his early manhood he had made a some-
what thorough acquaintance with more than one department of natural
history, and this makes it natural that his name was mentioned (and,
if he had permitted, would have been urged) by his friends for the
post of Naturalist to the government exploring expedition under Cap-
tain Wilkes. It explains, too, his success in a field he had then hardly
cultivated ; for the turning point in his career as a naturalist came
when, in 1837, as the result of a memorial of the Natural History So-
ciety to the General Court, the legislature authorized a Natural His-
tory Survey of the Commonwealth, and the Governor appointed Dr.
Storer one of the Commissioners to prosecute it. The several commis-
sioners divided the work between them, and as Dr. A. A. Gould, an
older and more experienced malacologist, was naturally assigned the
Mollusca, Dr. Storer undertook the description of the fishes and rep-
tiles of the State. He had previously paid some attention to one of
these groups, the fishes, as is shown by the justly severe criticism of
Smith's list of our species which he published the year before in the

390 DAVID HUMPHREYS STORER.

" Boston Journal of Natural History " ; but it is probable that his spe-
cial acquaintance with this part of our fauna only began at about tbat
time, when he was appointed one of the Curators of the Society's mu-
seum. Yet three years thereafter he published his report upon both
the groups, an octavo volume of two hundred and fifty-three pages.
Considering that these were just the years in which he was one of the
chief supports of the infant Tremont Street Medical School, which
gave systematic instruction throughout the year (the Harvard Medi-
cal School only for the four winter mouths), that he had the care and
toil of an engrossing profession, and that scarcely the nucleus of a col-
lection existed when he began his work, the result is certainly surpris-
ing. Through all the spring, summer, and autumn months, from five
o'clock in the morning until the breakfast hour, he might be found en-
gaged at the Society's museum over his specimens, snatching the early
hours out of a busy day ; every day, too, found him in the markets
and by the wharves, interesting the fishermen in his eager search for
strange forms of fish ; this contagious enthusiasm was one of the chief
sources of his success.

It was a token of his interest in and appreciation of this work that
Agassiz, when he first landed on our shores, went directly to Dr.
Storer from the house of Mr. Lowell, through whose invitation he had
come to America. Dr. Storer's house was for years the daily resort
of Agassiz and his Swiss associates, and with them his children grew
up on the most familiar terms.

This work upon our Massachusetts fishes and reptiles was thoroughly
done, equal to the best work of the time, and, like several other vol-
umes of the remarkable series published under the auspices of the
State, will ever remain a work of special value. That it was not com-
plete no one knew better than the author, and this doubtless it was
which led him to continue his investigations with the purpose of revis-
ing, enlarging, and perfecting it. To this he devoted all the forced
leisure of more than twenty-five years, publishing the work by instal-
ments in the Memoirs of the American Academy, with excellent illus-
trations, between 1855 and 1867 ; afterwards issuing it separately,
under the title of " A History of the Fishes of Massachusetts," as a
quarto volume of two hundred and eighty-seven pages and thirty-seven
plates.

In this work he redescribed, and with greater fulness, all the species
from our waters, and elucidated their natural history with the greatest
care, paying particular attention also to the economic side. His style
is lucid and simple, his descriptions perfectly clear and well ordered,

CYRUS MOORS WARREN. 391

the synonymy carefully worked out. There is as yet no complete
work of the kind for any part of the United States which surpasses it,
and it will ever remain a laud-mark in the ichthyological literature of
the country ; for it is a storehouse of facts, and it was the successful
collecting and simple presentation of facts whi^h made the volumes
of several of the earlier commissioners — Harris, Gould, Storer, and
Emerson — models of what natural history work of permanent value
should be.

Dr. Storer's other considerable publication, the " Synopsis of the
Fishes of North America," a quarto volume of nearly three hundred
pages, published in 1846, is of less value, because distinctly a work of
compilation, and he was not so skilled in the niceties of classification
as in the descriptions of the different specific forms and the study of
their histories; but it was the first considerable attempt to collate
existing material, and as such it had its importance and convenience.

A man full of enthusiasm and sympathy, fearless, impulsive and
generous, high-minded, high-spirited, and with a noble scorn of any-
thing mean, deceitful, or unjust, Dr. Storer endeared himself alike to
pupils and associates. No one who has known him will forget the
open, brilliant expression of his mobile countenance, his piercing,
friendly eye, the quick, impulsive speech, full of force and geniality ;
he was a friend worth making a sacrifice for, and not to be forgotten.
In 1829, he married Abigail Jane Brewer, sister of the ornithologist,
the late Dr. T. M. Brewer, by whom he had three sons and two
daughters. His wife died in 1885. His children survive him; two
of his sons have distinguished themselves in science, and have been
elected to membership in this Academy. Dr. Storer was the recipient
of many honors in his medical profession, a member of many learned
societies, and received from his Alma Mater the degree of Doctor of
Laws in 1876. At the time of his death he was the oldest physician
in Boston.

CYRUS MOORS WARREN.

Cyrus Moors Warren was born at Fox Hill, West Dedham,
Massachusetts, January 15, 1824. He died at Manchester, Vermont,
August, 13, 1891. He was a remarkably well defined example of that
particular type of the American character which has been admirably
depicted by Mr. Henry James in one of his best known novels.
Bold, ready, persistent, intelligent, with unusual aptitude for business
and for the affairs of ordinary life, and possessing decided administra-

392 CYRUS MOORS WARREN.

tive ability, he was none the less attracted instinctively by things high
and excellent, and he sought faithfully, according to his lights, for the
best which the world has to give. In his early years he devoted
himself with untiring energy to the accumulation of property ; but in
middle life he gave himself up to the service of science with the same
zealous ardor and with distinguished success. It then appeared that
he cared for money only as a means to worthy ends, for he was liberal
almost to a fault, and it was especially noticeable that he never shrank
from expense when it appeared that by freely employing money some
obscure point in science might be made clear. To his friends he was a
constant reminder of the truth of the Old World dictum, " L'Ameri-
cain ne se redoute a rien," and his work may well be regarded as a
symbol of great things which will come to be when Americans such as
he was shall more commonly than now happens give themselves up as
he did to scientific pursuits.

This type is distinctively a product of our Western States. Many
people at the East have no just conception of it. It was said indeed
by a Boston lady who had been accustomed all her life to the society
and the admiration of men wealthy, artistic, literary, and scientilic,
that she had never met or seen in her experience any such person as
Mr. James's hero. But it was an easy matter to prove that she had
not looked in the right place, even as Thoreau made answer to the
seeker of arrow-heads by stooping to pick one up from the road on
which they were walking.

Cyrus was the fifth son and the eighth child in the family of
eleven children of Jesse and Betsey (Jackson) Warren, who came of
old Massachusetts stock, of English origin, related in fact to the War-
rens and Jacksons whose names have so constantly been conspicuous
in the history of this State. Both of them belonged to well defined
branches of the original stocks. Jesse Warren, the father, a man of
decided ingenuity, was a blacksmith, who employed many men and
carried on establishments which must have been large for those days.
He became at length a manufacturer of ploughs also, which were
esteemed in their time. He invented the so called swivel, or side-hill
plough, and was, if not the first, among the first of New Engkmders to
make the working parts of ploughs of cast iron. Not having been
pecuniarily very successful at Dedham, the elder Warren bought a farm
at Peru, Bennington County, Vermont, in the very heart of the forests
of the Green Mountains, and established also a foundry, plough-shop,
and smithy there, in 1829, when the boy Cyrus was five years old.
The wildness of the place may be conceived of from the facts that one

CYRUS MOORS WARREN. 393

night wolves killed a number of sheep in a field close to the house,
and that the trunks of sweet-apple trees in the orchard were scratched
by the claws of bears which came to gather the fruit. In doing so
they left marks which made an abiding impression on the heart and
the mind of the boy. It was in this region that the early childhood
of our late associate was passed, and it was in such schools as the lo-
cality and the State could offer that his education was gained. When
he was thirteen years old his father again moved, to Springfield, Ver-
mont, and carried on an iron foundry there, which was totally destroyed
by fire two years later, to the complete impoverishment of the family.

Cyrus, as he grew older, — together with his next elder brother,
Samuel M. Warren, — became ambitious of obtaining a more liberal
education, and both of them directed their energies earnestly to this
purpose. For a number of years they supported themselves as best
they could by any work they could find to do. They taught schools
in the winters, and worked in hayfields during the summer vacations,
pursuing their studies meanwhile at every opportunity, in the early
morning and late at night, often under great difficulties, until the
elder brother, in the hope of more speedily gaining the desired end,
conceived an idea of improving the process of covering roofs with
tarred sheathing, which was then struggling into existence. Samuel
established works to this end at Cincinnati, Ohio, in 1846, and in the
course of the next year asked his brother Cyrus to join him. A part-
nership was soon formed by the two brothers, with the understanding
that, the moment the profits of the business should admit of it, the elder
brother should be at liberty to study a profession, thus carrying out his
fixed purpose from the beginning. The business succeeded so well
that Samuel soon entered a lawyer's office at Cincinnati, and after-
wards studied for a time at the Dane Law School in Cambridge. He
graduated in due course from the Cincinnati Law School, and was
admitted to the bar ; but afterwards became a minister and preached
at Brookline, Massachusetts, and for a number of years in London,
England.

Cyrus remained meanwhile in Cincinnati, and he was married there
in 1849 to Miss Lydia Ross. Other brothers had been called in to help
carry on the roofing business, and in due course Cyrus, in his turn,
found the purposed opportunity to devote himself wholly to study. He
moved to Cambridge with his family in 1852, and entered the Law-
rence Scientific School in the departments of Zoology and Chemistry.
His first meeting with Agassiz at this time was an important event in
his life. He never forgot the cordiality with which he was greeted, and

394 CYRUS MOORS WARREN.

he profited not a little from the advice which was then given him and
from the encouragement he received. Agassiz quickly recognized the
native force of the man, and sympathized with his thirst for knowledge.
He was so well pleased with his efficiency that he urged him to devote
his life to the study of natural history, and for a time Warren
seriously thought of doiug so ; but chemistry proved to have a yet
stronger claim upon him, and he thenceforth devoted himself to this
branch of science. After working two years longer at Cambridge in
the Chemical Laboratory, he took the degree of S. B., with high dis-
tinction, in 1855, having presented as a thesis the results of a study
which he had made of the chemical composition of brain, with esti-
mations of the amounts of sulphur, chlorine, and phosphorus therein
contained. He commended himself to his teachers and examiners so
heartily that immediately after graduation he was elected an honorary
member of the Phi Beta Kappa, on nomination of Benjamin Peirce,
seconded by Louis Agassiz, — being the first graduate of the Law-
rence Scientific School to whom this honor was accorded.

Soon after graduating from the Scientific School, Warren took his
family to Europe, and studied there during several years, first at Paris,
then at Heidelberg under Bunsen, at Freiberg in Saxony, at Munich
under Liebig, at Berlin under Heinrich Rose, and subsequently in
London, — all this in a purely scientific spirit, and with thorough enjoy-
ment of scientific research. It is noticeable that his work in Rose's
laboratory on compounds of Zirconium and Titanium is far enough
removed from any suggestion of utilitarianism. But though living in
an atmosphere of pure science, and devoting himself earnestly to
scientific study, he could not help noticing matters which might be of
advantage to his brothers and himself in their business, and in this way
he was led to the most important work of his life, — the separation and
the study of volatile hydrocarbons.

The Brothers Warren had used originally for their roofing purposes
the pitch of pine-tar ; but the great business success of the firm seems
to have depended largely upon their having turned their attention to
the coal-tar of gas-works at a time when this material was absolutely
without commercial value, and the makers of it were glad to give it
away to any one who would remove it from their premises. They
were the first in this country successfully to utilize on a large scale
what had previously been regarded as a waste product. Thus it
happened, long before any one had suspected that various substances
obtainable from coal-tar would ultimately be put to highly important,
uses in the arts, that the Warrens got control of all the tar produced

CYRUS MOORS WARREN. 895

in New York City, and in several other of the larger cities of this
country, aud had made contracts for long terms of years with many of
the largest gas-works, which gave them assured control of all the tar
which might be produced. Hence, when the auilin dyes came into
use, and a great demand arose for those portions of coal-tar naphtha
from which these dyes were made, the Warrens were peculiarly fa-
vorably situated for producing the naphtha, and gained large profits
by selling it.

Nothing could have been more natural than that the scientific mem-
ber of the firm should turn his attention to the question how best to
obtain these volatile products ; and nothing marks the great inventive
power of the man more clearly than the masterly way in which he
solved this highly iutricate problem. His process of "fractional con-
densation," as published in 1864 in the Memoirs of this Academy,
is admirable alike as a means of scientific research and as a techno-
logical method. This memoir, with its explanatory diagrams, was
widely copied in scientific journals, and an expert travelling in Europe
in 1870 found the process in common use there in the distilleries of
tar. In some instances the managers of these works knew that they
were using Warren's invention, while others professed ignorance as to
its origin, while freely admitting its excellence.

By means of this apparatus Warren dissected, so to say, in a most
thorough and exhaustive manner the more volatile portions of the tars
and oils which are obtained by the distillation of coal and of wood, as
well as the naphthas of petroleum ; and in so doing he solved well-
nigh completely a chemical problem which had been regarded as one
of the most intricate of the time. He claimed with justice for his
apparatus that it enabled the chemist, occupied with the study of mix-
tures of volatile, non-decomposable liquids, to prove the negative as
well as the positive, since by means of it it is easy to separate and
obtain in a state of almost absolute purity the several components of
the mixtures, and at the same time to prove that the mixtures con-
tained no other substances than those actually isolated.

One important result of these researches was the wholly unlooked for
discovery that the more volatile portions of Pennsylvanian petroleum
contain two distinct series of homologous hydrocarbons (C„H2n+2),
which run parallel one with the other. The boiling-points of the
contiguous members of either series differ by 30° C. But while the
several members of the first series boil at 0°, 30°, 60°, 90°, etc.,
the members of the other series boil at 8°, 38°, 68°, 98°, and so on.
That is to say, the members of the two series boil at intermediate

396 CYRUS MOORS WARREN.

points, and the complete separation of them had been as good as im-
possible before the invention of Warren's method of fractioning. In
point of fact, the existence of the double series had caused no little
annoyance to chemists, in that they had been able to separate at one
time some of the members of one series, and at other times members
of the other series, with the result that much confusion prevailed. All
uncertainty as to this matter was done away with at once by the pub-
lication of Warren's memoir. His discovery was seen to be true the
moment attention was called to it. The causes of the previous con-
fusion became manifest, and many of the earlier statements which had
seemed to be conflicting were found to be fairly harmonious. He
found furthermore that the less volatile portion of petroleum, instead
of containing, as had been supposed, higher homologues of the bodies
just now referred to, is composed of hydrocarbons of another class,
C„Hn + 2; and of these defines he separated three, boiling respect-
ively at 175°, 196°, and 216° C. The difference between the
boiling-points of contiguous members of this third series he found
to be about 20°, and not 30°, as in the other series. Fortunately,
an elaborate statement of these results will soon appear, for a com-
pleted memoir relating to them was found among Warren's papers
after his death.

It is interesting to note the fact that the high degree of purity of the
products obtained by Warren compelled him to take special pains to
analyze them with particular accuracy. The ordinary methods of
ultimate organic analysis had seemed sufficient for the compara-
tively impure substances studied by his predecessors, — perhaps because
the errors due to the impurities known to be present were supposed to
be larger than those inherent to the processes of analysis. But the
inadequacy of the old methods was shown at once on attempting to
study pure hydrocarbons by means of them, and Warren was forced
to turn aside for a moment from his legitimate work in order to invent
new methods of combustion in oxygen gas, and subsequently to devise
a new method of determining the density of vapors.

The years devoted by Warren to the study of the hydrocarbons were
the most fruitful of his scientific life. From 1863 to 1866, he had in
Boston a thoroughly well equipped private laboratory, in which he
gave himself up wholly to research. Eight papers were communicated
by him to the Academy at that time, and were published in its Memoirs
and Proceedings. Besides the discovery of new substances and the
better definition of others which were already known, these papers
describe novel and ingenious methods of his invention for the analysis

CYRUS MOORS WARREN. 397

of organic compounds, for the estimation of sulphur and of chlorine,
and the determination of vapor densities. They contain among other
things a critical discussion of the methods of determining boiling-points,
and an exposition of the inaccurate methods and conclusions of some
of his predecessors. One of his conclusions was, " that the boiling-
point difference for the addition of C H2 in homologous hydrocarbons
is generally 30° C, — which is a much larger difference than had been
commonly supposed."

Among the details of these researches will be found a statement re-
lating to the separation of hydrocarbons from oil of cumin, which,
though nothing more than an incident touched upon solely for the
sake of elucidating the main line of the research, may well be cited as
an example of neatness, completeness, and elegance in chemical work.
Due account being taken of the very small amount of material at his
disposition, this particular analysis well illustrates Warren's accuracy
and his skill as a manipulator.

It is a matter for lasting regret that Warren was unable to carry
out his plans for studying the large collection of pure volatile hydro-
carbons which he accumulated during this period, and which for
many years subsequently he kept in store. As an example of these
things may be mentioned an extremely volatile, elusive, liquid sulphur
compound from coal-tar, which he separated in a state of purity and
had partially studied. Indeed, his process for determining sulphur in
organic compounds was devised for the purpose of analyzing this sub-
stance. As it boiled freely at the temperature of melting ice, it had
to be condensed by means of freezing mixtures. It was evidently a
compound of considerable scientific interest. He called it provisionally
" alliole." It is said that by taking pains to free benzol completely
from this contamination, the commercial value of the benzol was
increased. The purified benzol suited the anilin-makers better than
the ordinary article.

From Boston, Warren moved to Brookline, and established another
private laboratory there, which was for the time and for his purposes
remarkably complete in its equipment. He fully intended to continue
his scientific investigations, but so many adverse influences accumulated
that he was unable to carry out his plan. For one thing, he was ap-
pointed to the Professorship of Organic Chemistry at the Massachusetts
Institute of Technology., though he resigned the position after a year
or two because it consumed too much of his time. He was continu-
ally appealed to also by his business associates, who besought him
to help them in new enterprises, and to deliver them from difficulties,

398 CYRUS MOORS WARREN.

which he did frequently with signal success. His partners had missed
him not a little during the term of his highest scientific activity ;
and afterwards, in a period of great commercial depression, they were
only too anxious to be helped by " so good a man of business." It
must be admitted that his associates had good cause to wish to have
him always with them, for he was a conspicuously able and indomi-
table man, born to command success. To him the failure of an under-
taking or loss of fortune meant little more than a new incentive to
energy and to labor ; and the customary and to-be-expected result of
his activity was the recovery of all that had been lost, and more.
Though ordinarily mild of manner and extremely good-natured, this
determination of character was plainly written on his face ; and it
was remarked by an assistant in his Boston laboratory, in the winter
of 1863, that Warren's mouth must have been copied for making up
the photographs of General Grant, which were in that year beginning
to be freely displayed.

As a matter of course, no man could long lead a life of such un-
tiring activity. There was no apparent slackening of his mental
powers even to the end, but his physical ability to labor sensibly dimin-
ished after the very severe strain and long-continued anxiety to which
he was subjected during the period of commercial depression which
succeeded the panic of 1873. As his physical powers diminished,
he suffered frequently from severe nervous headaches, which were
manifestly symptomatic of fatigue. But " it took much to discourage
him," and to the last he kept himself accurately informed upon all
matters of importance relating to a very large business, and did much
of the thinking of the firm, and all of its most important correspond-
ence. His partners and he himself knew well that he understood
their affairs better than any one else, and could better than either of
them attend to the business. The burden upon him was much in-
creased in 1880 by the death of his brother, Herbert M. Warren,
who was lost on the " Narragansett," in Long Island Sound. In 1888,
when much enfeebled physically by overwork, he had a paralytic stroke,
from which he never recovered. Two winters passed at Nassau, and
a couple of summers spent in absolute rest in the Adirondacks and
in Vermont, failed to restore him, and he died quietly in the summer
of 1891.

It would be difficult to write in any way of Warren's scientific career,
without making some mention of his business interests. For that
matter, many of the results of his scientific labors are upon record, to
be seen by every one, and it is instructive to consider in what respect

CYRUS MOORS WARREN. 399

this work was helped or hindered by the business relations. The fact
that his firm so extensively controlled the coal-tar of the country forced
them, as has been said, to prepare the naphthas therefrom when a de-
mand for these substances arose, and afterwards, in like manner, they
were called upon to produce large quantities of anthracene when this
compound was required for making alizarin. At a much earlier
period they had prepared naphthalin in a condition of almost absolute
purity, with the ideas that this solid substance might be put to use by
glass-blowers as a convenient fuel to throw into their " glory holes,"
instead of the "dead oil " used for producing a strong reducing flame,
and that it could be moulded into candles, which might be burned out
of doors in spring-candlesticks, — both of which plans were brought to
naught by the speedy introduction of coal-oil and petroleum, and of
paraffin obtained from these oils.

Another venture, which ended in failure, deserves mention as a
matter of historical interest ; namely, that the Warrens undertook to
manufacture anilin colors in this country at a very early period (1862),
when the price of these compounds was extremely high. To this end
they built a factory at South Boston, and equipped it with costly and
ingenious apparatus devised by C. M. Warren. This factory had
actually been put into operation, and was producing nitrobenzol, when
the price of the anilin dyes suddenly fell to a very low figure, from
which point they have never risen again to anything like the former
standard. The Warrens were thus compelled to relinquish their
undertaking. The reduction in price had been brought about by
certain English manufacturers who sought to crush a rival in that
country.

From being engaged in all these enterprises Warren had constant
opportunity to make note of points that specially needed elucidation in
the behavior of the chemical substances operated upon, and he was
doubtless able to gain time in many cases as regards his scientific in-
vestigations by making preliminary rough studies at the manufactory.
Moreover, he could have at any time, for the asking, unlimited sup-
plies of any materials he might wish to investigate, either in the
crude or in the partially purified condition ; and he could always be
sure that his materials were precisely what they purported to be. It
should be remembered always, when Warren's work on hydrocar-
bons is contrasted with that of his predecessors, that he had enor-
mous advantages over most chemists both as to his methods and his
materials. For example, it will be seen at a glance that it was easier
for him than for most other investigators to make the discovery of his

400 CYRUS MOORS WARREN.

parallel series of hydrocarbons in the more volatile part of Pennsyl-
vanian petroleum, because he had opportunity to operate upon mate-
rials which had never been subjected to any treatment with chemicals.
His competitors, working upon commercial products which had been
" purified " by agitation with oil of vitriol, were at a manifest disad-
vantage. There are published results of such investigations, which go
to show that a large part of the members of one of the series had
actually been removed in some way from the petroleum before it was
subjected to scientific examination.

In the course of time, when their contracts for coal-tar had lapsed,
and competition between the distillers of tar became sharp, the War-
rens paid less attention than they had formerly done to this branch
of their business, and turned their energies more particularly to the
asphaltum of Trinidad, aud to the rectification of this substance by a
process which consists essentially in driving off some thirty per cent of
water, which is entangled in the crude pitch as taken from the lake,
and removing some other mechanical impurities by processes of set-
tling or skimming. The product thus obtained, and known as refined
asphalt, is used for electrical purposes, as well as for paving and for
roofing. For some uses the purified asphalt is mixed with a certain
proportion of petroleum residues that are left in the stills when crude
petroleum is rectified.

In the carrying out of these changes Cyrus Warren took a lively
interest and gave valuable aid. But it was characteristic of the man
that during all the long period of business strain his mind was full of
scientific interests and ideas. It is greatly to be regretted that the
results of these cogitations and of the experiments made from time to
time during this period have never been published. Warren himself
felt that several of them should be made known to the world, and he
fully intended in his last years to present to the Academy one or
more papers relating to these matters. He never ceased to lament
that the exigencies of business, in which he had become inextricably
entangled, kept him from entire devotion to scientific pursuits. But
perhaps the keenest of his regrets was felt when, after he was finally
disabled, his physician forbade him to enter his laboratory to do a last
work for science in gathering from his note-books and connecting the
fragments of the more important labors which had been performed
during the intervals of his business activity.

One of his ideas was to make a systematic scientific analysis of that
portion of the heavier products of coal-tar which is known as anthra-
cene oil. Anthracene itself is obtained from this grease by pressing

CYRUS MOORS WARREN. 401

the mass in a hydraulic press at a tolerably definite and constant tem-
perature maintained by steam heat, by which means various crystalline
substances other than anthracene are expelled ; and Warren proposed
to isolate each of these compounds by a process of fractional liquefac-
tion or of methodized eliquation. He had gone so far as to have had
constructed especially for this purpose, and at very considerable ex-
pense, a small compact hydraulic press which carried a copper jacket
which was to be filled with water that could be kept at any desired
temperature by means of gas lamps. The diameter of the jacket was
enough larger than that of the plate of the press to admit of lamps being
put under it to heat the water. In this way the mixture of crystals
could be pressed again and again, at some one definite temperature,
until the substance which remains solid at this temperature had become
so pure that nothing more could be squeezed out from it ; then the
matters which had remained liquid at that temperature could be pressed
at another temperature until another substance had been isolated, and
so on as long as any of the material was left. This process seems to
have reached an eminently hopeful stage of development, when work
upon it was interrupted by increased business cares which followed
the death of his brother, Mr. Herbert M. Warren, in 1880. It is
evident that a manageable process of this kind would find ready appli-
cations in the study of waxes, fatty bodies, camphors, paraffins, and
some resins, as well as in that of the heavy products of tar. Possibly
even the very intricate problem as to the composition of the mixture
of oxidized fatty acids, which are concerned in the technical pro-
cess of currying leather, and in the old method of fixing the color
known as Turkey-red upon cotton cloth, might be solved in this
way.

This Academy was held by Cyrus Warren in profound respect.
He was proud to be a member of it, and he appreciated very highly
the scientific atmosphere which he found here. This remark is true
also of our lamented associate Ferrel, whose early life had been akin
to Warren's in many respects. It was a great pleasure to these men
— independent and self-sustained though they both were — to be in
touch with scientific associates. They knew that here at least their
aspirations would be sympathized with and their efforts be justly ap-
preciated ; and it will be well for us all to remember how much such
men may be encouraged by an organization of high tone and character
competent to hold them steadily to their best ideals.

In Warren's last will and testament were found written the follow-
ing words : —

vol. xxvu. (n. p. xix.) 2C>

402 CYRUS MOORS WARREN.

" I give and bequeath to Harvard University fifty shares of the stock
of the Warren- Scharf Asphalt Paving Company [now equal to $5,000 at
the least], to be held by the said University, or to be sold and con-
verted into money, and the proceeds thereof to be securely invested, and
the income, dividends, interests, or profits of said stock, or of the pro-
ceeds, of the same, to be devoted by the said University, in its discretion,
to the promotion of chemical research, or the advancement of chemical
science. . . .

" I give and bequeath to the American Academy of Arts and Sciences
of Boston one hundred shares of the capital stock of the Warren-Scharf
Asphalt Paving Company [equal to $10,000], the proceeds, dividends,
and income thereof to be applied by the said Academy, its trustees or
directors, in their discretion, for the encouragement and advancement of
research in the science or field of chemistry. . . .

" I give and bequeath to said American Academy of Arts and Sciences
fifty shares of the capital stock of the Warren-Scharf Asphalt Paving
Company [equal to $5,000], the proceeds thereof to be applied to or towards
a building fund for the purpose of erecting a building for the use of the
library of said Academy, and for holding the meetings of said Academy;
the same to be used in erecting such a structure when, in the opinion of
the directors or trustees of said corporation, a sum sufficient shall be
realized to justify such erection."

Papers by Cyrus Moors Warren.

1. Ueber einige Zirkonerde- und Titan-Saure-Verbindungen: —

A. Ein neues Schwefelsaures Zirkonerde-Salz, etwas Kali

enthaltend.

B. Schwefelsaures Zirkonerde-Kali.

C. Schwefelsaures Titan-S'aure-Kali. Poggendorff's Annalen,

1857, CIL, p. 449.

2. On a Safety-lamp, for Laboratory Use. American Journal of Science,

1862, (2d series,) XXXIII. 275.

3. On a Process of Organic Elementary Analysis, by Combustion in a

Stream of Oxygen Gas. Proc. Amer. Acad., VI. 251. (8 March,
1864.)

4. On a Process of Fractional Condensation; applicable to the separa-

tion of Bodies having small differences between their Boiling-
points. Mem. Amer. Acad., IX. 121. (10 May, 1864.)

5. Researches on the Volatile Hydrocarbons: —

A. Hydrocarbons from Coal-tar Naphtha (p. 137).

B. Hydrocarbons from Oil of Cumin and Cuminic Acid

'(p. 149).

C. On the Influence of C2H2 upon the Boiling-points in Homol-

ogous Series of Hydrocarbons, and in some Series of their
Derivatives ; with Critical Observations on Methods of

SERENO WATSON. 403

taking Boiling-points (p. 15G). Mem. Amer. Acad., TX.
135. (11 Oct., 1864.)

6. On a New Process for the Determination of Sulphur in Organic Com-

pounds, by Combustion with Oxygen Gas and Peroxide of Lead.
Proc. Amer. Acad., VI. 472. (14 March, 1865.)

7. On a New Process of Organic Elementary Analysis for Substan-

ces containing Chlorine. Proc. Amer. Acad., VII. 84. (31 Jan.,
1866.)

8. Note on an Improved Apparatus for the Determination of Vapor

Densities by Gay-Lussac's Method; being a Modification of Bun-
sen's Apparatus for measuring Aqueous Vapor. Proc. Amer.
Acad., VII. 99. (10 April, 1866.)

9. Hydrocarbons of Pennsylvania Petroleum. American Journal of

Science, 1868, (2d series,) XLV. 262.

10. (Posthumous.) On the Volatile Hydrocarbons in Pennsylvania Pe-

troleum. Proc. Amer. Acad., XXVII. 56.

11. (Posthumous.) Note on a Criticism of the Author's Apparatus for

Fractional Condensation. Proc. Amer. Acad., XXVII. 89.

12. (With F. H. Storer.) Examination of a Hydrocarbon Naphtha, ob-

tained from the Products of the Destructive Distillation of Lime-
soap. Mem. Amer. Acad., IX. 177. (9 Aug., 1865.)

13. (With F. H. Storer.) Examination of Naphtha obtained from Ran-

goon Petroleum. Mem. Amer. Acad., IX. 208. (9 Aug., 1865.)

SERENO WATSON.

Sereno Watson, a Fellow of this Academy, died at his home in
Cambridge on March 9, 1892.

To most of his associates here he was known only as a regular
attendant at our meetings, and an occasional contributor to our Pro-
ceedings, presenting his communications, which were of a technical
character, by title.

His co-laborers in Natural History recognized him as a critical
student in the department of Descriptive Phamogamic Botany, who
enriched our volumes by the results of work of a high order.

Those who were engaged in neighboring fields of botanical investi-
gation knew him as a faithful friend of few words. He was observed
by them to carry on his researches in silence, seldom alluding to any
special task in hand until it drew near completion, and even then only
briefly. He was always ready to interrupt his studies to assist others
in theirs ; he would enter with unconcealed pleasure into the plans of
others, but without ever speaking of his own.

Hence it happens that his intimate friends, when called upon to

404 SERENO WATSON.

speak in his memory, think first of the reserve and silence in which he
walked. The question arises in their minds at the outset, how far is
one justified in breaking through a reserve which was unbroken by him,
and revealing to others the features of his blameless and useful life.
This question is answered in part by a few letters written by our
friend to relatives, who were sometimes naturally importunate for de-
tails of his movements ; some of these memoranda have been placed
at my disposal for the execution of the present task. Beyond the
limits of these letters, and of others sent me by his relatives and
nearest friends, the present sketch will not venture to pass, until it
reaches that period of his life which becomes a part of the history of
American Botany.

Sereno Watson was born at East Windsor Hill, Connecticut, on
December 1, 1826. His father, who had been a merchant in New York
City, passed the last years of his life on a farm which he had inherited.
On this farm Sereno's boyhood was passed, and here he developed a
vigorous physique. Until his very last year, he was capable of sus-
tained effort with little fatigue, from which it came to pass that he
was wont to tax his strength to its utmost limit, often imprudently
or with only slight regard to consequences.

The class in which he graduated at Yale, in 1847, was one of the
largest and strongest at that period. In the words of one of his class-
mates, he " was always highly spoken of by those who knew him, but,
as in later years, was so reticent as to his personal history that prob-
ably no one knew much about him." He was considered a good
scholar. He distinguished himself especially in classics, taking prizes
for Latin composition and translation.

In 1851 Watson wrote thus to a relative : "Three years and a half
ago I graduated, and I doubt if there was ever a mortal cursed with
more diffidence, less energy, or a head fuller of strange notions, and
who, to make the matter worse, was so fully conscious of it all. The
most that 1 have done since then has been partially to overcome these
drawbacks to all success. On leaving college I knew not what to do.
I had no predilection for any of the professions. The only course left
open to me for getting a living was teaching school." To this work
he went at once, and entered on a very varied experience. He taught
common or district schools in Connecticut, Long Island, and Rhode
Island, and in the Academies at Allentown, Penn., and Tarrytown,
N. Y

While teaching in Tarrytown, he wrote to a relative as follows :
" My experience has taught me many a lesson which I probably would

SERENO WATSON. 405

not soon have learned otherwise, and school teaching is not the least
improving of schoolmasters. It is true I have lost time in gaining a
profession, and shall lose more, but I scarcely regret it."

In the same letter he says : " I might say more of myself, my plans
and my opinions. Many an episode, pleasing, displeasing, and ridicu-
lous, miffht be inserted in the brief history upon the last two pages,
but I dislike to speak so much of myself. It is perhaps a fault in my
character, but I am rarely frank enough to confide to any one what only
relates to myself alone."

Very early in his career as a teacher, he began the study of medi-
cine, and, after the fashion of that time, with a practitioner as a pre-
ceptor,,— at first with Dr. Watson of Scantic,and afterwards with Dr.
Sill of Windsor. Of the next year he writes : " I lived through the
winter of 1849-50 in New York," attending medical lectures at New
York University, "and left with a much diminished respect for medical
practitioners and professors in general, apart from medicine itself,
which is a noble profession."

In 1851 he taught in Tarrytown ; in 1852 he was at home, farming
and studying.

Of the next few years, his brother Louis, a physician, gives the fol-
lowing account : " I wrote to him to come to Quincy, Illinois, where
I was established, to study with me, see practice, and practise for him-
self, on cases that I could give him, and such as were likely to apply
to him. He accepted, and was preparing to leave East Windsor, when
his uncle, Rev. Dr. Julius A. Reed, of Davenport, Iowa, one of the
founders of Iowa College, and one of the Trustees, induced him to go
there instead, act as Tutor in the College, and teach in the Preparatory
School. He reached there in September, and remained as Tutor till
July, 1854. He then came to Quincy, studied in my office under my
direction, and attended urgent calls in my absence. I was city phy-
sician at that time, and turned over to him most of that business, and
gave him a small salary. He got some business in respectable fami-
lies of his church, and more among the poor, from whom he collected
but little. A physician of about seventy years fell and broke his
femur. Sereno attended him throughout with good success, without
once consulting me, and I think I knew nothing of it at the time. I
remember only two cases of disease which he asked me to see with
him, — both serious and complicated, and one of which proved fatal.
His practice of medicine there was entirely satisfactory to his patients
as far as I know. He was not legally qualified to practise, of course,
but he was better informed than some who were. My brother Henry,

406 SERENO WATSON.

late of Northampton, then in Greensboro, Alabama, president of an
insurance and banking company, offered him a position as clerk
or cashier, and he left Quincy in 1856, which was the end of his
doctoring."

His brother Louis answers also a question which may be noted at
this point : " As to his botanical studies I know but little. I suppose
they were taken up among his studies for the medical profession.
When he was at Quincy I occasionally picked up plants in the Missis-
sippi bottoms, taking them to my office for examination. If I could
not readily determine them by the only Botany I then had (Beck's), I
referred them to him. He had more patience than I had, and deter-
mined them. When in the United States service in the Civil War, in
the Southern Mississippi, Tennessee, and Missouri, I picked up plants
unknown to me, and, having no books, I sent them to him to learn what
they were, and received replies naming them."

He remained in the South engaged in insurance and banking until
the breaking out of the Civil War. During this time he must have
devoted a good share of his leisure to the examination of the plants
around him, for he later manifested a great degree of interest in any
rarities coming from that region.

Dr. Henry Barnard, then editor of the "Journal of Education,"
gave him on his arrival at the North, in 1861, some work connected
with the Journal, all of which was satisfactorily done. Of this stage
in Watson's life, the venerable Dr. Barnard speaks most affectionately.
He recalls with vividness Watson's interest in plants, and his eager
desire to aid beginners in their work of determining species. But he
did not think of him at all as a botanist at this time ; he seemed just
as likely to turn his hand to one pursuit as to another.

In 1866, Watson entered the Sheffield Scientific School of Yale, at
the age of forty, as a student, but not to pursue botanical investiga-
tions. He went there to carry on studies in chemistry and mineral-
ogy. He impressed his teachers in these departments as being capable
and diligent. The possible, or rather probable design for which these
special studies were undertaken must have been to fit him for a resi-
dence in California, which he had now in mind. The studies had a
practical turn. His nephew remembers distinctly that during this
time they made a journey together to Loudville, Conn., to examine an
abandoned lead and silver mine, and still another visit to an aban-
doned iron mine.

These facts are here mentioned not so much to indicate the range of
his studies as to point out the thoroughness with which he endeavored

SERENO WATSON. 407

to prepare himself for the next work in view. But he was now on the
eve of a total and unforeseen change of plan, by which he soon en-
tered on a sphere of activity in which all his previous training was
utilized. This change of base and plan are best described in his
own words. The account is thoroughly characteristic. It is dated
San Francisco, April 28, 1867.

" The request in your last letter that I should ' open ' would have
received prompter attention had there been anything to say for myself
beyond conjecture. There is at least this much certain at present,
that I have left New England again and am safely landed in this capital
city of the Land of Gold. I have been ready to start on short notice
for several months, but one thing after another turned up which in-
volved the possibility of my not coming at all, so that I was kept in a
state of uncertainty, and not able to say definitely whether I was
coming here or not. One proposition was made to me to take ten
thousand dollars and go into the drug business at Selma, but this fell
through. Another was to buy a saw-mill and go into the lumber
business with Mr. Weruyss at Mobile. A week's delay of the mails
flanked that movement. Mr. Barnard offered me a clerkship in the
new Educational Department at Washington, of which he is appointed
Commissioner, and this I declined. One Friday I found myself clear
of all questions of the kind, and, to give no time for any more to come,
I determined to take the next steamer, which sailed on Monday. To
pack up, close up, say good by, and get to New York by Saturday
evening, left of course very little spare time. I wrote no letters, and
did not stop to see friends in East Windsor or Hartford, but made my
escape by the flank, and am consequently now here. . . .

" I am not yet settled, and do not know where it will be nor at what
business. I started with a dozen strings to my bow, some of which
snapped at the first trial. I am confident that some of the rest will
do better. I have no idea of going to the mines."

It appears that at first Watson thought of farming in California.
Even in the early years after graduation from college he had con-
templated taking a farm in Connecticut with his brother, and this
occupation always had great attractions for him. But suddenly he
gave up the idea of purchasing a farm in California, and started from
Woodland across the Sierra Nevada to join the Geological Survey of
the Fortieth Parallel. Doubtless he had heard something of the pro-
posed survey from the leader of the expedition. Clarence King, who
passed a part of the previous winter in New Haven.

He reached the camp on the Truckee River on a July night, coming

408 SERENO WATSON.

in covered with dust, foot-sore, with his hoots and pack slung over
his shoulder, and presenting the appearance of one unused to rough
mountaineering. But he would not rest, eat, nor wash until he had
arranged with the chief of the party for some sort of work to do.
He was at first put to plant collecting in connection with miscellane-
ous topographical work. The botanist of the expedition, Mr. Bailey,
now Professor of Botany at Brown University, had been too ill to
botanize in the desert, and this work fell naturally into the hands of
Watson. Under date of August 18 he writes: "I am informed to-
night of a change in my position. I have worked thus far without any
pay heyond my expenses, and giving my special attention to botany,
hut I am now assured of a salary, small as yet, but better than nothing,
and am detailed to the topographical department."

One of the members of the party writes : " Watson was an ex-
ceedingly hard worker, — on the tops of the mountains, out in the
broad sage-brush flats, down in the canons, and tramping amongst
the hot springs and alkali soils for plants. What impressed me the
first year was not only his energy, but the systematic way in which
he searched all kinds of soils and exposures for variations in plant
life."

Of him the leader of the expedition says : " He impressed me as
a man of work, grimly and conscientiously in earnest. . . . He smiled
only as a forced concession to humor. Everything pertaining to
his duty was sacred. . . . He soon learned to ride, and after the
first anxieties regarding his duties had worn off he began to enjoy the
campaign life and the weird scenery with the greatest enthusiasm.
Bailey grew more and more subject to the camp illness, and at last
gave up and went home to the East. ... I then installed Wat-
son in charge of the Botany. He was then as nearly perfectly
happy as I have ever seen a human being. There were periods of
at least five minutes at a time when the hereditary New England
grimness vanished from his face, and he wore a free, careless air, as if
his grandfather might have come from at least as far south as Vir-
ginia. If these excessive moments were rare, the general tone had
grown calmly happy, and so I believe he remained till his connection
with the Fortieth Parallel ceased."

Another expression by his chief, states what was equally true of
his herbarium investigations : " He worked without the least nervous
excitement or hurry, but continuously, and for a calm man rather
rapidly."

The report on the botanical studies, and the description of the col-

SERENO WATSON. 409

lections made at this time, were prepared in the herharium of Pro-
fessor Eaton, at New Haven and at Cambridge. But one can see
that the notes were made on the spot where the plants were found,
and nothing was left for the memory to lose. Watson wrote thus in
a letter concerning the scope of the collection : " My work is at
Professor Eaton's house, where all my plants are. I spend from two
to twelve hours a day upon them, and it is going to be an everlasting
job to work them up. It is the best and largest collection that has
ever been brought in by any government party, and promises to yield
a fair proportion of new species."

The Report was published in 1871, and confirms fully the state-
ment made in the note which I have read. Not only were the
collections the largest, but the notes respecting the surroundings of
the plants were more detailed than any that had ever been returned
from our Western plains. The notes constitute a fund of information
for those who would know the habits of our desert plants.

The last portion of the Report was prepared at Cambridge, in the
Gray Herbarium that was his home from 1870. Here he attacked
and solved some of the most puzzling questions regarding North
American plants, and the results of these researches are given for the
most part in the volumes of our Proceedings. His other investiga-
tions and his separate works are noticed in the bibliography which is
appended to this sketch.

At the time he was taken ill, he was engaged in the attempt to
complete the Synoptical Flora of North America, left unfinished by
Dr. Asa Gray. For this work his extensive acquaintance with our
Western Flora and his conservative views regarding nomenclature
specially fitted him. For the most part his botanical practice and
principles were in perfect accord with those of his predecessor. His
maturity of thought, his wide training in many and diverse fields, and
his independence in deciding questions seemed to render his service in
the completion of the Synoptical Flora on the lines laid down by its
designers absolutely indispensable. At present, the Flora stands as a
broken column, twice interrupted in construction.

No sketch of Watson's life, however brief, would be complete
without some mention of three journeys other than those of the
Survey already described.

One of these was in behalf of the Forestry division of the Tenth
Census. For a few friends he prepared a charming sketch detailing
his adventures. The sketch gives a glimpse of the keen pleasure
which he took in wandering, and his untiring powers of observation.

410 SERENO WATSON.

A second journey was to Guatemala. This study of the tropics
was botanically profitable, but it impaired his health. By a curious
coincidence he passed considerable time in iuvestigating the Flora of a
country from which his classmate, Captain Donnell Smith of Baltimore,
has obtained such interesting botanical results.

His third journey was to Europe. I had the great pleasure of ac-
companying him, and of seeing his delight at the gardens of the Old
World. But he shrank here, as always, from even the slightest sacri-
fice of any time for merely social matters. With two exceptions, he
declined all the attentions which were tendered him.

Foreign distinctions were beginning to be bestowed upon him in the
last years of his life. He had for some time been a highly valued
member in our American academies and associations. But dis-
tinctions and honors of all kinds were to him almost a matter of
indifference. He accepted the honors less for himself than from a
regard for the feelings of others. Nothing was more foreign to his
nature than any scramble for priority ; hence his reclamations are few.
He was averse to holding any office ; but when he was forced to submit
to this infliction, he surrendered at discretion, and performed his duties
not only acceptably and faithfully, but gracefully.

No one who came in contact with him could fail to see how warm
and deep were his sympathies. The writer had the great privilege of
seeing Watson almost every day for about twenty college years, and
he can bear willing testimony to the truth of the following words,
written by one of the classmates of 1847, Professor Jesup of Dart-
mouth College : —

" His was one of those true and gentle natures that can always be
trusted. He dreaded most of all to be a source of anxiety to his
friends, not realizing that a fuller expression of his hopes and fears
and plans would often have afforded them vastly more relief than
pain. ... In the family he was self-denying and very thoughtful
of the interests of others, doing many a kind act, the recipient of
which knowing nothing of the source from which it came. . . .
He was a man of decidedly religious character, though he could seldom
be induced to take any public part in religious exercises. He was
fond of his church, and for years instructed a Bible class.

" He seemed more deeply impressed than almost any one I hav
ever known, that life is short, and that the field is growing more and
more extensive every day. He believed that he must work, while
the day lasted and with no reference to any reward except the knowl-
edge that he had done what he could. I doubt whether he ever
thought of posthumous fame."

SERENO WATSON. 411

But as we all know, this unsought reward of posthumous fame is
his. That it should have come to one who did not fall upon his life
work until middle age shows how well that life work was done after
it was well iu hand. One of his friends has fitly said: " Had he died
twenty years after graduation, the world would have known little of
him, and his classmates would have considered his life a failure.
That long period, however, comprised years of diversified preparation,
which enabled him to bring to his chosen task thoroughly trained
powers and gave him a range of knowledge drawn from the study
of several sciences."

A loyal son of Yale College, he was also devoted to the College of
his adoption. Almost his last request was that his remains might be
placed in the Harvard University grounds at Mount Auburn. There
they rest, near by the tomb of his associate and constant friend, Asa
Gray.

The following list of Dr. Watson's papers lias been prepared by
J. A. Allen, Ph. B., Assistant at the Gray Herbarium, Cambridge.

United States Geological Exploration of the Fortieth Parallel, Clarence
King, Geologist in charge. Vol. V. Botany. By Sereno Watson,
aided by Prof. Daniel C. Eaton, and others. Illustrated by a map
and forty plates. Washington, 1871.

List of Plants collected in Nevada and Utah, 1867-69 ; numbered as dis-
tributed. United States Geological Exploration of the Fortieth Par-
allel, Clarence King, U. S. Geologist, in charge. Sereno Watson,
Collector. Washington, 1871.

Contributions to American Botany. I. New Plants of Northern Arizona
and the Region adjacent. American Naturalist, Vol. VII. pp. 299-
303, 1873.

Contributions to American Botany. II. Revisions of the extra-tropical
North American Species of the Genera Lupinus, Potentilla, and Oeno-
thera. Proc. Amer. Acad., Vol. VIII. pp. 517-618, 1873.

Contributions to American Botany. III. On Section Avicularia of the
Genus Polygonum. American Naturalist, Vol. VII. pp. 662-665,
1873.

Note on Chenopodium leptophyllum, Nutt. Bulletin Torrey Botanical
Club, Vol. IV. p. 63, 1873.

Contributions to American Botany. IV. Revision of the North American
Chenopodiace?e. Proc. Amer. Acad., Vol. IX. pp. 82-126, 1871.

List of Plants collected in Nevada, Arizona, and Utah, upon Lieut. G. M.
Wheeler's Survey, in 1871 and 1872. By Sereno Watson. (In Cata-
logue of Plants collected in the years 1871, 1872, and 1873, with De-
scriptions of New Species. Geographical and Geological Explorations

412 SERENO WATSON.

and Surveys West of the One Hundredth Meridian, Lieut. Geo. M.
Wheeler in charge. Washington, 187-4.)

Contributions to American Botany. V. Revision of the Genus Ceauothus,
and Descriptions of New Plants, with a Synopsis of the Western Spe-
cies of Silene. Proc. Amer. Acad., Vol. X. pp. 333-350, 1875.

Some Notes and Descriptions of New Species, by Sereno Watson,
inserted in Botanical Observations in Southern Utah in 1874, by
Dr. C. C. Parry. American Naturalist, Vol. IX. pp. 267-273 and
346-351, 1875. "

Botany of California. Vol. I. Polypetahe, by W. H. Brewer and
Sereno Watson. Gamopetalse, by Asa Gray. Cambridge, Mass.,
1876.

Contributions to American Botany. VI. 1. On the Flora of Guadalupe
Island, Lower California. 2. List of a Collection of Plants from
Guadalupe Island, made by Dr. Edward Palmer, with his Notes.
3. Descriptions of New Species of Plants, chiefly Californian, with
Revisions of certain Genera. Proc. Amer. Acad., Vol. 'XL pp. 105-
148, 1876.

Historical Note on Beans. Bulletin Torrey Botanical Club, Vol. VI.
p. 104, 1876.

Contributions to American Botany. VII. Descriptions of New Species
of Plants, with Revisions of Lychnis, Eriogonum, and Chorizanthe.
Proc. Amer. Acad., Vol. XII. pp. 246-278. 1877.

Note on Iris. American Naturalist, Vol. XI. pp. 306-307, 1877.

Bibliographical Index to North American Botany ; or Citations of Au-
thorities for all the recorded Indigenous and Naturalized Species of
the Flora of North America, with a Chronological Arrangement of
the Synonymy. Part I. Polypetahe. No. 258, Smithsonian Miscella-
neous Collections. Washington, 1878.

Contributions to American Botany. VIII. The Poplars of North Amer-
ica. American Journal of Science and Arts, Vol. XV. pp. 135-136,
1878.

Report upon United States Geographical Surveys West of the One Hun-
dredth Meridian, in charge of Lieut. Geo. M. Wheeler. Vol. VI.
Reports upon the Botanical Collections made in Portions of Nevada,
Utah, California, Colorado, New Mexico, and Arizona, during the
years 1871, 1872, 1873, 1874, and 1875. By J. T. Rothrock and
others. With thirty plates. The Leguminosa? by Sereno Watson.
Washington, 1878.

Review of Gray's Synoptical Flora of North America. American Natu-
ralist, Vol. XII. pp. 686-689, 1878.

Characterized Description of Lilium Parryi, by Sereno Watson ; inserted
in A New Californian Lily, by Dr. C. C. Parry. With two plates.
Proc. Davenport Acad, of Nat. Sciences, Vol. II. pp. 188-189. Daven-
port, Iowa, 1880.

SERENO WATSON. 413

Contributions to American Botany. IX. 1. Revision of the North
American Liliacese. 2. Descriptions of some New Species of North
American Plants. Proc. Amer. Acad., Vol. XIV. pp. 213-303, 1879.

Botany of California. Vol.11. By Sereno Watson. Cambridge, Mass.,
18S0.

Contributions to American Botany. X. 1. List of Plants from South-
western Texas and Northern Mexico, collected chiefly by Dr. E.
Palmer in 1879-80. — I. Polypetalse. 2. Descriptions of New Species
of Plants from our Western Territories. Proc. Amer. Acad., Vol.
XVII. pp. 316-382, 1882.

Contributions to American Botany. XI. 1. List of Plants from South-
western Texas and Northern Mexico, collected chiefly by Dr. E.
Palmer in 1879-80. — II. Gamopetalae to Acotyledones. 2. Descrip-
tions of some New Western Species. Proc. Amer. Acad., Vol. XVIII.
pp. 96-196, 1883.

Review of Henry John Elwes's Monograph of the Genus Lilium. Ameri-
can Journal of Science and Arts, Vol. XXV. pp. 82-83, 1883.

Manual of the Mosses of North America. By Leo Lesquereux and Thomas
P. James. With six plates illustrating the Genera. (Revised before
publication by Sereno Watson.) Boston, 1884.

Contributions to American Botany. XII. 1. A History and Revision
of the Roses of North America. 2. Descriptions of some New
Species of Plants, chiefly from our Western Territories. Proc. Amer.
Acad., Vol. XX. pp. 324-378, 1885.

Contributions to American Botany. XIII. 1. List of Plants collected
by Dr. Edward Palmer in Southwestern Chihuahua, Mexico, in 1885.
2. Descriptions of New Species of Plants, chiefly from the Pacific
States and Chihuahua. 3. Notes upon Plants collected in the De-
partment of Yzabal, Guatemala, February to April, 1885. — I. Ranun-
culacere to Connaraceae. 4. Notes upon some Palms of Guatemala.
Proc. Amer. Acad., Vol. XXI. pp. 414-468, 1886.

Contributions to American Botany. XIV. 1. List of Plants collected
by Dr. Edward Palmer in the State of Jalisco, Mexico, in 1886.
2. Descriptions of some New Species of Plants. Proc. Amer. Acad.,
Vol. XXII. pp. 396-481, 1887.

Our Tripetalous Species of Iris. Botanical Gazette, Vol. XII. pp. 99-
101, 1887.

The Genera Echinocystis, Megarhiza, and Echinopepon. Bulletin Torrey
Botanical Club, Vol. XIV. pp. 155-158, 1887.

A Point in Nomenclature. (Synonymy of Cliftonia nitida, Gaertn. fil.)
Bulletin Torrey Botanical Club, Vol. XIV. p. 167, 1887.

Contributions to American Botany. XV. 1. Some New Species of
Plants of the United States, with Revisions of Lesquerella (Vesica-
ria), and of the North American Species of Draba. 2. Some New
Species of Mexican Plants, chiefly of Mr. C. G. Pringle's Collection

414 SERENO WATSON.

in the Mountains of Chihuahua, in 1887. 3. Descriptions of some
Plants of Guatemala. Proc. Amer. Acad., Vol. XXIil. pp. 249-287,
18S8.
Notes, and Notices of new or little known Plants Garden and Forest,
Vol. L, New York, 1888: —

Iris tenuis, p. 6, fig. 3.

Note on our Native Irises, p. 18.

Lilium Grayi, p. 19, fig. 4.

Aquilegia longissima, p. 31, fig. 6.

Iris bracteata, p. 43, fig. 8.

Phlox adsurgens, p. 66, fig. 11.

Chionophila Jamesii, p. 79, fig. 15.

Cypripedium fasciculatum, p. 90, fig. 16.

Rosa minutifolia, p. 102, fig. 22.

Hymen ocallis humilis, p. 114, fig. 23.

Brodisea Bridgesii, p. 125, fig. 24.

Hymenocallis Palmeri, p. 138, fig. 25.

Rocky Mountain Cypripediums, p. 138.

Delphinium viride, p. 149, fig. 29.

Heliconia Choconiana, p. 161, fig. 31.

Camassia Cusickii, p. 172, fig. 32.

Amelanchier alnifolia, p. 185, fig. 34.

Pitcairnia Jaliscana, p. 195, fig. 35.

Pitcairnia Palmeri, p. 209, fig. 38.

Philadelphus Coulteri, p. 232, fig. 40.

Amelanchier oligocarpa, p. 245, fig. 41.

Phlox Stellaria, p. 256, fig. 42.

Cypripedium Calif ornicum, p. 281, fig. 45.

Erythronium Hendersoni, p. 316, fig. 50.

Tigridia Pringlei, p. 388, fig. 61.

Phlox nana, p. 413, fig. 66.

Hibiscus lasiocarpus, p. 425, fig. 68.

Rosa Nutkana, p. 449, fig. 70.

Berberis Fendleri, p. 460, fig. 72.

Pentstemon rotundifolius, p. 472, fig. 73.

Berberis Fremonti, p. 496, fig. 77.
Note. — Is there a second species of Conradina ? Bulletin Torrey Bo-
tanical Club, Vol. XV. p. 191, 1888.
An erratum (concerning Cacalia tussilaginoides, HBK.) to Contribution

XIV. Botanical Gazette, Vol. XIII. p. 322, 188S.
Manual of the Botany of the Northern United States, including the District
east of the Mississippi and north of North Carolina and Tennessee.
By Asa Gray. Sixth Edition. Revised and extended westward to
the 100th Meridian by Sereno Watson and John M. Coulter, assisted
by specialists in certain groups. With twenty-five plates, illustrating

SERENO WATSON. 415

the Sedges, Grasses, Ferns, etc. New York, Cincinnati, and Chicago,
188!). Second issue, with corrections, 1890.
Contributions to American Botany. XVI. 1. Upon a Collection of
Plants made by Dr. E. Palmer, in 1887, about Guaymas, Mexico, at
Muleje and Los Angeles Bay in Lower California, and on the Island
of San Pedro Martin in the Gulf of California. 2. Descriptions of
some New Species of Plants, chiefly Californian, with Miscellaneous
Notes. Proc. Amer. Acad., Vol. XXIV. pp. 36-87, 1889.
The Century Dictionary, an Encyclopedic Lexicon of the English Lan-
guage, prepared under the Superintendence of William Dwight
Whitney. Botany, A — G, by Sereno Watson. New York, 1889.
Notices of new or little known Plants. Garden and Forest, Vol. II.,
New York, 1889: —

Neillia Torreyi, p. 4, fig. 84.
Rosa humilis, var. triloba, p. 76, fig. 93.
Helianthus mollis, var. cordatus, p. 136, fig. 100.
Calochortus Obispoensis, p. 160, fig. 101.
Portlandia pterosperma, p. 208, fig. 105.
Cordia Greggii, var. Palmeri, p. 233, fig. 106.
Brodisea Palmeri, p. 244, fig. 107.
Rosa Engelmanni, p. 376, fig. 121.
Tigridia buccifera, p. 412, fig. 125.
Contributions to American Botany. XVII. 1. Miscellaneous Notes
upon North American Plants, chiefly of the United States, with De-
scriptions of New Species. 2. Descriptions of New Species of
Plants from Northern Mexico, collected chiefly by Mr. C. G. Prin-
gle, in 18S8 and 1889. Proc. Amer. Acad., Vol. XXV. pp. 124-163,
1890.
On the Genus Eriogynia. With plate. Botanical Gazette, Vol. XV.

pp. 211-242, 1890.
The Relation of the Mexican Flora to that of the United States. Ab-
stract published in the Proceedings of the American Association for
the Advancement of Science, Vol. XXXIX. pp. 291-292, 1890.
Notices of new or little known Plants. Garden and Forest, Vol. III.,
New York, 1890: —

Rosa foliolosa, p. 100, fig. 22.
Lycoris squamigera, p. 176, fig. 32.
Schubertia grandiflora, Mart. & Zucc, p. 368, fig. 48.
Contributions to American Botany. XVIII. 1. Descriptions of some
new North American Species, chiefly of the United States, with a Re-
vision of the American Species of the Genus Erythronium. 2. Descrip-
tions of new Mexican Species, collected chiefly by Mr. C. G. Pringle,
in 18S9 and 1890. 3. Upon a wild Species of Zea from Mexico.
4. Notes upon a Collection of Plants from the Island of Ascension.
Proc. Amer. Acad., Vol. XXVI. pp. 121-163, 1891.

416 GEORGE W. CULLUM.

Note changing the Name Oligonema to Golionema. Botanical Gazette,

Vol. XVI. p. 267, 1891.
Pentstemon Haydeni, n. sp. Botanical Gazette, Vol. XVI. p. 311, 1891.
Atriplex corrugata, n. sp., and Notes on Ranunculus glaberrimus, Hook.

and Ranunculus Macauleyi, (iray. Botanical Gazette, Vol. XVI.

pp. 345-346, 1891.
A New Astragalus. Zoe, Vol. III. p. 52. San Francisco, April, 1892.
On Nomenclature. (In press.) Botanical Gazette, Vol. XVII., June,

1892.
Dr. Watson was engaged at the time of his death in the continuation of

the Synoptical Flora of North America.

ASSOCIATE FELLOWS.
GEORGE W. CULLUM.

General George "VV. Culluji was born in the city of New
York on the 25th of February, 1809. While he was quite young his
family removed to Meadville, Pennsylvania, where he received an
excellent preparatory education which well fitted him for admission to
the Military Academy at West Point. He was entered, July 1, 1829,
and graduated third in his class of forty-three members, July 1, 1833.
He was then promoted in the army to Brevet Second Lieutenant,
Corps of Engineers, in which corps he was further promoted to
Second Lieutenant, April 20, 1836; Captain, July 7, 1838; Major,
August 6, 1861; Lieutenant Colonel, March 3, 1863; and Colonel,
March 7, 1867. He was appointed Brigadier General of United
States Volunteers, November 1, 1861, and received the brevet rank of
Major General, U. S. Army, March 13, 1865, in recognition of his ser-
vices during the Rebellion. July 13, 1874, he was retired from active
service according to law, being over the age of sixty-two years.

General Cullum served actively over forty years as a constructor of
military works and light-houses, as commander of Engineer troops,
as Instructor and Superintendent of the United States Military Acad-
emy at West Point, as Aide de Camp and Chief of Staff to the Gen-
eral in Chief of the Army, and as member of various boards to devise
seacoast and other fortifications, river and harbor improvements, etc.

He was distinguished as an author of numerous military, scientific,
historical, and biographical works, and was a leading spirit in several
scientific societies.

GEORGE W. CULLUM. 417

He died of pneumonia at his residence in New York City, on the
28th of February, 1892.

Between the time of his graduation and the breaking out of the
Mexican War, he served as Assistant Engineer in the construction of
Fort Adams at Newport Harbor, as Superintending Engineer of the
construction of Fort Trumbull and Battery Griswold in New London
Harbor, and Forts Independence, Warren, and Wiuthrop in Boston
Harbor, of the pier and lighthouse at Goat Island, Newport Harbor,
and as Assistant to the Chief Engineer at Washington.

During the Mexican War he was charged with devising and con-
structing sapper, miner, and ponton trains for our armies, and prepar-
ing a text-book on military bridges.

After the war he was placed on duty at the Military Academy as
commandant of Sappers, Miners and Pontoniers, Instructor of Prac-
tical Military Engineering, etc. Here he remained until 1850, when
his health was so broken down that he was compelled to go abroad on
a sick leave of absence, which he spent in travelling through Europe,
Asia, Africa, and the West Indies. The climate of Egypt completely
restored him. In 1852 he resumed his former duties at West Point,
and in 1853-54 he also superintended the modification of the Treasury
Building in New York City. From 1855 to the breaking out of the
Civil War he served as Superintending Engineer of the construction
and repair of Fort Sumter, Castle Pinckney, Fort Macon, Fort Cas-
well, Fort Moultrie, Clark's Point, Fort Adams, Fort Trumbull,
Battery Griswold, Willet's Point, and Fort Schuyler, and of the har-
bor improvements of Charleston. In 1858 he was a member of the
Board on the Defences of New York Harbor.

During the Civil War he served as Aide de Camp to General Scott,
as Chief Engineer and Chief of Staff of the Department of Missouri
and of the Mississippi, and as Chief of Staff of General Halleck, then
in command of the Army. In 1861-62 he conducted extensive mili-
tary operations, more especially of an engineering character. His
position as Chief of Staff was one of great responsibility, and afforded
him an opportunity to exercise great influence on all the military
operations of the war. In addition to these duties, his talents were
required in those branches in which he was especially proficient, such
as organizing systems of fortification and improving the ponton service,
revising the programme of instruction at the Military Academy, etc.
In this work he was sometimes associated with other officers, and the
reports of the boards upon which he served mark one of the most
important eras in the history of modern warfare. These reports were
vol. xxvu. (n. s. xix.). 27

418 GEORGE W. CULLUM.

the first to announce and formulate the radical changes that were de-
manded by the increased power of modern ordnance, and have formed
the basis of all subsequent methods that have been adopted by the
armies and navies of America and Elurope. As General Cullum's
talents and tastes rather inclined him to the literary part of the work,
he was generally selected to prepare these reports. From 1861 to
18(34 he was a member of the United States Sanitary Commission.

In 1864 he was appointed Superintendent of the United States
Military Academy. From 1866 to 1868 he was stationed in New
York City as a member of the Board of Engineers on New York
Harbor, and from 1868 to 1874 as a member of the permanent
board, whose duty it was to prepare all schemes of fortification re-
quired for the defence of the seacoast of the United States, and to
advise the Chief of Engineers on all important points connected with
river and harbour improvements. A complete list of his military
duties is given in his own Biographical Register, Vol. I. pp. 535-537.

After his retirement from active service, in 1874, he devoted his
time to literary work with untiring energy. He has been Vice-Pres-
ident of the American Geographical Society since 1874, and Pres-
ident of the Geographical Library Society of New York since 1880.
He was a member of the Board of Managers of the New York Asso-
ciation for the Improvement of the Condition of the Poor from 1880
to 1882; of the Farragut Monument Association from 1880 to 1881 ;
a delegate to the conference of the Association for the Reform and
Codification of the Law of Nations, held at Cologne in 1881, and of
the International Geographical Conference, held at Venice, September.
1881. He has been a member of the Association of the Graduates of
the United States Military Academy since 1870 ; a Corresponding
Member of the Massachusetts Historical Society since 1883 ; an As-
sociate Member of the American Academy and of the American
Historical Association since 1885.

The following extracts from the Bulletin of the American Geo-
graphical Society, and from the Annual Report of the Association of
the Graduates of the Military Academy, show the high esteem in
which he was held by his associates.

" Resolved, that in the death of our first Vice-President. Major Gen-
eral George W. Cullum, U. S. Army, this society has lost one of the
most eminent, useful, and devoted of its members. No one who has been
connected with it during the forty years of its existence had a more com-
prehensive view of the importance of the inquiries to which its labors
have been directed, or saw more clearly how much it might accomplish

GEORGE W. CULLUM. 419

for the benefit of mankind, if its resources were adequate to the great
field before it. For the seventeen years during which he acted as Vice
President, his efforts were untiring to make it what it ought to be, and
what he belived it ultimately would become. He took upon himself a
large share of those executive labors that are indispensable to the success-
ful management of such an institution, overlooked its extensive corre-
spondence and advised respecting it, gave much of his attention to the
publication of the journal, and scarcely a day passed during those seven-
teen years that he did not come to the Society's house to supervise some
matter of detail. The narrow limits of a resolution will not admit of an
enumeration of all that he has done for our institution. We can only ex-
press our deep sense of our loss, our appreciation of his wide and accurate
knowledge, and our high regard for him as a man." *

" General Cullum was a leading spirit in the organization of the Asso-
ciation of Graduates, in 1870. He was its most enthusiastic supporter.
and it is safe to say that without his aid and assistance in its manage-
ment the Association would not have survived the infant stages of its
existence and lived to attain such a robust majority. General Cullum
prepared more of the obituaries published in our annual reports than any
twenty-five other graduates. He was ever ready to respond to a request
to write the history of deceased graduates. He became a member of
the Executive Committee in 1871, and was the Chairman from 187S
till his death." f

List of General Cullum's Publications.

Military Bridges with India Rubber Pontons, 1849.

Register of the Officers and Graduates of the United States Military Acad-
emy, 1850.

Translation of Duparcq's " Elements of Military Art and History," 1863.

Systems of Military Bridges, 1863.

Biographical Register of the Officers and Graduates of the United States
Military Academy, 1867, 1879, 1890.

Campaigns and Engineers of the War of 1812-15 against Great Britain.

Struggle for the Hudson during the American Revolution, in the " Nar-
rative and Critical History of America."

Fortification and Defences of Narragansett Bay, 1888.

Feudal Castles of France and Spain.

Numerous contributions to the publications of Societies, etc.

General Cullum's military writings were highly esteemed by those
of his own profession, and the translation of Duparcq's " Military Art

* Bulletin Amer. Geog. Soc, March, 1882.
t Beport, Ann. Beunion, 1892.

420 GEORGE W. CULLUM.

and History," which was presented in a most attractive form at the
time of the Civil War, was eminently useful to the officers of the
volunteer army.

His historical writings embodied the results of original and ex-
haustive research in the military history of several campaigns of the
Revolution and of the War of 1812. He not only collected all
documentary evidence on the subject, but devoted much time to a per-
sonal examination of battle fields and sites of ancient defences, and
brought the light of his own military study and experience to bear
upon the situation. These writings are accordingly of great value to
historical and military readers, from the fact that these very fields are
more likely than any others to become the theatre of future military
operations.

Of all General Cullum's works, his Biographical Register is the
most important. General Wright in his obituary notice says : " This
work, which in its third edition is extended to include the class which
graduated in 1890, is indeed a fitting monument to his memory. While
so universally appreciated by the graduates of the Academy, it may
be confidently asserted that no other of their number could be found
to undertake so herculeau a labor, which nothing but his will and un-
tiring energy, combined with his love for the school to which he owes
so much, could have carried to a successful conclusion." Every source
of information, official and private, was exhausted to make the work
accurate and complete; archives were ransacked, tons of manuscript
were examined, letters by thousands were written, and almost count-
less interrogatories were put whenever there was a hope of gleaning
any information at all reliable. Although General Cullum was an
exceedingly frugal man, he not only defrayed the cost of publishing
this work from his private funds, but made in his will a bequest of
twenty thousand dollars for its continuance. All future American
historians will depend upon it for important data. The Military
Academy numbers among its graduates many who have been dis-
tinguished in all branches of civil life. The number who have made
their impress upon the history of the country, and occupied high posi-
tions of trust in political life, or become distinguished as civil engineers
or scientists, is hardly realized outside of their own circle. Accordingly,
in reading the Register in its final form we follow the thread of Ameri-
can history throughout the nineteenth century.

From his economical habits, General Cullum had amassed a large
fortune, which was still further increased by his marriage late in life
with the widow of General Halleck, granddaughter of General Alex-

GEORGE W. CULLUM. 421

ander Hamilton. Leaving no immediate heirs, he bequeathed the
greater part to the institutions in which he had been interested. The
most important items were $250,000 for the erection of a Memorial
Hall at West Point, stipulating in his will that the sword, bust,
and portrait of General Halleck should be deposited there ; $20,000
for mural tablets and painted portraits of deceased officers and
graduates ; $20,000 for the continuance of Cullum's Biographical
Register of the Graduates of the Military Academy, to be published
decennially ; $10,000 to the Association of Graduates of the Academy ;
and $100,000 for a hall for the American Geographical Society.

From this sketch it appears that, apart from his professional duties,
he devoted his whole life to a few great objects. He was deeply im-
pressed with the necessity of thorough military education. He be-
lieved that the country had already been saved or benefited in more
than one instance by the skill and loyalty of the graduates of West
Point, that a complete and unbiased record of their services would
be the surest way to establish this belief, and that the certainty of
such record in the past and future would also add to the esprit de corps
and sense of responsibility of all graduates. He had no sympathy for
the conduct of the few that joined the Confederate States in the
Civil War, but stated the facts in unequivocal terms, and dropped
their military record without further comment.

His historical writings were all directed to general questions of the
military defence of the country against foreign invasion. His geo-
graphical labors absorbed the rest of his available time.

The wealth which economy and other circumstances had placed
within his grasp was not squandered in personal indulgence, but
reserved for posthumous work, directed to the same general purposes,
excepting the portion bequeathed to relatives and friends.

It is not surprising that he appeared cold and undemonstrative
to those who were not in perfect sympathy with his work and his
method of conducting it. He had a' few intimate friends to whom he
was steadfastly attached. He was an excellent judge of character,
and his criticisms of men and motives were often astonishing in view
of the relations into which he had been personally thrown with them.
He was interested in humanity at large, and this combined with his
wide and varied experience, his general information, his refined man-
ner, and a certain occult sense of humor to make him a very inter-
esting companion.

422 JOHN C. FREMONT.

JOHN C. FREMONT.

It is a singular circumstance in the career of John C. Fremont that
his important services as an explorer and his contributions to science
were brought to a close when he was scarcely more than thirty-four
years of age. He was born in the State of Georgia in the year 1813,
and from the year 1842 to the year 1846 inclusive he undertook and
carried to a successful result three expeditions from the Mississippi
River across the plains, and finally over both chains of the Rocky
Mountains, to the Pacific Ocean. Mr. Jefferson, during his adminis-
tration, had realized the importance of securiug "open over-land
commercial relations with Asia," as stated in one of his messages to
Congress ; and, as a preparation for establishing such relations with
Asia, he originated and organized the expedition of Lewis and Clarke,
whose duty it was to trace the affluents of Columbia River now known
as Snake River and Clarke's Fork.

Fremont's early education was obtained under the charge largely of
Dr. John Roberton, a Scotchman who had been educated at Edin-
burgh, and who had established himself at Charleston, S. C, as a
teacher of the ancient languages. Dr. Roberton says that in the
space of a year Fremont read four books of Caesar, six books of Vir-
gil, nearly all of Horace, and two books of Livy ; and in Greek, all
the Grasca Minora, about half of the Graeca Majora, and four books
of Homer's Iliad. At the end of a year he entered the Junior Class
of Charleston College, where he gained high standing for study and in
scholarship; but for insubordination he was expelled from the College.

In 1833 he was appointed Teacher of Mathematics in the Navy, and
made a cruise to South America, which occupied about two and a half
years of time. While absent, a law was passed creating the office of
Professor of Mathematics in the Navy, for which Fremont upon his
return was examined, and appointed. Without entering upon the
duties of the place, he declined the position, and accepted the post
of Surveyor and Railroad Engineer upon the railway line between
Charleston and Augusta. In 1838 and 1839 he was associated with
M. Nicollet, a Frenchman and a member of the Academy of Sciences,
in an exploring expedition over the Northwestern prairies and along
the valley of the Mississippi. During his absence, he was appointed
by President Van Buren a Second Lieutenant in the Corps of Topo-
graphical Engineers. Upon his return from the Upper Mississippi, and
for the period of a year, he was engaged with Nicollet and Mr. Hass-
ler, then the head of the Coast Survey, in the arrangement of the sci-

JOHN C. FREMONT. 423

entific materials that had been collected during the expedition, and in
the preparation of a map and a report. In 1842 he was directed by
Colonel Abert, the Chief of the Topographical Corps, to make an
exploration of the Northwestern frontier of the State of Missouri to
the Rocky Mountains, and with special reference to an examination of
what was known as the South Pass in those mountains. This expedi-
tion was on a small scale, consisting of twenty-one men only, most of
whom were of French extraction. In this expedition, he traced the
waters of the Platte to the South Pass, which he reached the 8th of
August. It was stated by Dr. Linn, then a Senator from the State of
Missouri, that " over the whole course of the road barometrical obser-
vations were made by Mr. Fremont to ascertain the elevations both of
the plains and of the mountains, astronomical observations were made
to ascertain latitudes and longitudes, the face of the country was
marked as arable or sterile, the facility of travelling and the practica-
bility of routes noted, the grand features of nature described and some
represented in drawings, military positions indicated, and a large contri-
bution to geology and botany was made in varieties of plants, flowers,
shrubs, trees, and grasses, and rocks and earths, which were enumer-
ated." The second expedition, of May, 1843, was upon a larger
scale, and it was not completed until the month of July, 1844. He
was directed to extend his survey across the continent, on the line of
travel between the State of Missouri and the tide-water region of the
Columbia. In its execution, much more ground was covered than
had been contemplated in the order. Fremont was the first person
that visited the basin of the Great Salt Lake who was able to fur-
nish a scientific and accurate description of the region. Von Hum-
boldt, in his work entitled " Aspects of Nature," (pp. 32-34,) has
given a summary of the results reached by Fremont in his first and
second expeditions, as follows : —

" Fremont's map and geographical researches embrace the immense
tract of land extending from the confluence of the Kansas River with
the Missouri to the cataracts of the Columbia, and the Missions of Santa
Barbara and the Pueblo de los Angeles in New California, presenting a
space amounting to 28 degrees of longitude (about 1,360 miles) between
the 31th and 45th parallels of north latitude. Four hundred points have
been hypsometrically determined by barometrical measurements, and for
the most part astronomically; so that it has been rendered possible to
delineate the profile above the sea's level of a tract of land measuring:
3,600 miles, with all its inflections, extending from the north of Kansas
to Fort Vancouver and to the coasts of the South Sea (almost 720 miles
more than the distance from Madrid to Tobolsk). As I believe I was

424 JOHN C. FREMONT.

the first who attempted to represent, in geognostic profile, the configura-
tion of Mexico and the Cordilleras of South America, — for the half-per-
spective projections of the Siberian traveller, the Abbe Chappe, (Chappe
d'Auteroche, Voyage en Siberie, fait en 1761, 4 vols., 4th ed., Paris, 1768.)
were based on mere, aud for the most part on very inaccurate, estimates
of the falls of rivers, — it has afforded me special satisfaction to there find
the graphical method of representing the earth's configuration in a verti-
cal direction, that is, the elevation of solid over fluid parts, achieved on
so vast a scale. In the mean latitude of 37° to 43°, the Rocky Mountains
present, besides the great snow-crowned summits, whose height may be
compared to that of the Peak of Teneriffe, elevated plateaux of an extent
scarcely to be met with in any other part of the world, and whose breadth
from east to west is almost twice that of the Mexican highlands. From
the range of mountains which begin a little westward of Fort Laramie, to
the farther side of the Wahsatch Mountains, the elevation of the soil is
uninterruptedly maintained from 5,000 to upwards of 7,000 feet above
the sea level ; nay, this elevated portion occupies the whole space be-
tween the true Rocky Mountains and the Californian snowy coast range
from 34° to 45° north latitude. This district, which is a kind of broad
longitudinal valley, like that of Lake Titicaca, has been named the
Great Basin by Joseph Walker and Captain Fremont, travellers well ac-
quainted with those western regions. It is a terra incognita of at least
128,000 English square miles, almost uninhabited, and full of salt lakes,
the largest of which is 3,940 Parisian (or 4,200 English) feet above the
level of the sea, and is connected with the narrow Lake Utah (Fremont,
Report of the Exploring Expedition, pp. 154 and 273-276), into which the
'Rock River' (Timpan Ogo in the Utah language) pours its copious
stream."

Fremont's third expedition was commenced, August 16, 1845, under
instructions to explore the interior of the region known as the Great
Basin, and the maritime parts of Oregon and California. The first
important incident of that expedition was the message of General Cas-
tro, Governor of California, ordering Fremont to leave the territory.
This was in the month of March, 1846. At the moment, Fremont
refused to obey the order, and proceeded to fortify his camp, where he
raised the United States flag, aud remained for about three days. On
further consideration, however, he left his camp and proceeded north
towards Oregon. In the early part of the month of May he was over-
taken by a messenger named Neal, who informed him that Lieutenant
Gillespie, an agent of the government at Washington, was on his way,
charged with the delivery of letters, and with verbal instructions from
the authorities. Upon receipt of this information, Fremont changed
his course, and on the second day met Gillespie, who brought only a

JOHN C. FREMONT. 425

letter of introduction from the Secretary of State, Mr. Buchanan, with
letters and papers from Senator Benton. From Gillespie he learned
that it was the purpose of the authorities to ascertain the disposition
of the inhabitants of California, to conciliate their feelings in favor of
the United States, and to counteract as far as possible any designs of
the British government upon that Territory. Fremont made his way
to the settled parts of California, near Monterey, where he found Com-
modore Sloat in command of a United States fleet. In co-operation
with him, and largely through Fremont's agency, the Mexican author-
ities were dispersed, the flag of the United States was raised at Mon-
terey and other points, and all was accomplished before information
was received of the existence of war between the United States and
Mexico. These proceedings were justified by the government of the
United States. In the mouth of December following, Brigadier Gen-
eral S. W. Kearny arrived in the Territory, and ultimately there was
a conflict between him and Commodore Stockton, who had succeeded
Commodore Sloat, as to the command of the forces in California.
Until the arrival of Kearny, Fremont had been acting under the or-
ders of Commodore Stockton, had raised troops, and had received from
him the appointment of Governor of the Territory. General Kearny,
in asserting his authority as Commander in Chief, ordered Fremont to
raise troops, and to submit himself to his orders. This Fremont de-
clined to do, giving as his reason that he had acted under Commodore
Stockton, that it was their duty to adjust their differences, and that
until they had done so he should act under the orders of Commodore
Stockton. This course on his part led to his arrest while on his way
to Washington, and his trial by a court martial upon three charges :
"1st, mutiny ; 2d, disobedience of orders ; and 3d, conduct prejudicial
to good order and discipline." On these charges he was convicted, and
sentenced by the court martial to be dismissed from the service. Six
of the officers who were of the court recommended him to the clem-
ency of the President. The President disapproved of the findings of
the court as to the charge of mutiny, but expressed the opinion that
the second and third charges were sustained by the proofs ; but that,
in consideration of the valuable services of Lieutenant Colonel Fre-
mont, the penalty of dismissal from the service was remitted. When
the findings of the court were announced, and the action of the Presi-
dent was made known to Fremont, he wrote a letter to the Adjutant
General resigning his commission as Lieutenant Colonel in the Army,
and giving as a reason that he could not, by accepting the clemency of
the President, admit the justice of the sentence.

426 THOMAS HILL.

It is not easy, from a legal point of view, to justify the action of the
President. If the conduct of Fremont in refusing to recognize the
authority of General Kearny was an offence, it must have rested upon
the fact that Kearny exhibited to him evidence which should have sat-
isfied a reasonable person that he had authority from the President to
take command of the military forces in California ; and if such author-
ity was exhibited to Fremont and he refused obedience, his refusal
constituted the crime of mutiny. The other offences charged against
Fremont would have followed as a matter of course ; but in the ab-
sence of proof that he was guilty of mutiny, there was no evidence
whatever on which the minor charges could be sustained. Thus ended
Fremont's military services and his career as an explorer when he was
less than thirty-four years of age.

Fremont's subsequent career may be considered under three heads.
First, in business affairs, in which, apparently, he was unsuccessful.
Next, he was the first candidate of the Republican party for the office
of President of the United States. His acceptance of the nomination,
and his letters and statements touching the policy and purposes of the
new organization were not merely formal, but they were pronounced
declarations in favor of the movement, with clear expressions in har-
mony with the object of the party, which was the prevention of the
extension of slavery in the Territories. Although a Southern man by
birth, his devotion to the freedom of the Territories was as ardent as
that of Lincoln, or any of the other leaders of the time. Finally, in
the Civil War, he made a tender of his services to the government, and
as Major General, and in command of the forces in the Department of
Missouri, he issued a proclamation of emancipation of the slaves within
his jurisdiction. This proclamation was countermanded by the Presi-
dent, and for the sufficient reason that he reserved to himself the abso-
lute control of the question of the abolition of slavery in the seceding
States and within the lines of our armies. It cannot be said that
Fremont's military career was marked by any signal successes, but
there can be no doubt of his ardent devotion to the cause of the
country.

THOMAS HILL.

The father of Thomas Hill was Thomas Hill, who came to this
country from England in 1791. He was a Unitarian, and came to
America to enjoy larger freedom of thought, speech, and action than
was tolerated in Non-conformists at the epoch of the Birmingham riot.

THOMAS HILL. 427

He established himself as a tanner in New Brunswick, N. J., and after-
ward served for many years as Judge of the Court of Common Pleas.
In 171)7 he married as a second wife Henrietta Barker, a grand-niece
of Rev. Joshua Toulmin (D. D., H. U. 1794), an eminent Unitarian
minister. Her father had left Eugland on account of the persecution
to which he had been subjected because of his religious faith and
his sympathy with Dr. Priestley. Of this marriage, Thomas, the ninth
and youngest child, was born, on the 7th of January, 1818. He in-
herited from his father a robust physical constitution, and mental pow-
ers of a high order. His early education was chiefly under the charge
of his sisters, who had the sole care of him after his mother's death in
1824. He was an indefatigable reader in his boyhood, and attributed
the formation of his scientific tastes to the reading of Franklin's and
Erasmus Darwin's works at the age of twelve. The more logical
statement would be, that without a native proclivity to science no boy
of twelve would read such books. He went to school from his ninth
to his twelfth year. His father died in 1828, and, as he left his family
with slender provision for their support, Thomas in 1830 was placed
as an apprentice in a newspaper office, whence was issued his first lit-
erary production in the form of a poetical New Year's Address to the
patrons of the paper. In 1833 he was sent for a year and a half to an
Academy near Philadelphia, of which his oldest brother was the Prin-
cipal. He then became an apothecary's apprentice, and remained in
that employment more than three years and a half.

Young Hill had from a very early period looked upon the Christian
ministry as the only profession which he was willing to choose for his
life work ; and when his brothers found that this was not a mere boy-
ish fancy, but, so far as it could be, a settled purpose, they did what
they could to enable him to realize it. He was already an advanced
scholar in mathematics, conversant with the physics and chemistry of
the time, and to some degree an adept in botany and zoology ; but he
knew not a word of any language except his own. He commenced his
preparation for college in May, 1838, and in August of the following
year entered the Freshman Class of Harvard University, having studied
first with Rev. Rufus P. Stebbins of Leominster, and then for a few
months at the Leicester Academy. He passed his entrance examina-
tion with but one condition, and that was in arithmetic, in which he
was probably by far his examiner's superior. I think that I knowT
how and why he was thus conditioned. The examination in arith-
metic then consisted in the solution of problems, or, to use the ver-
nacular, in doing sums on the spot. With his habit of prompt mental

428 THOMAS HILL.

calculation he undoubtedly omitted two thirds of the intermediate steps
required by the rules of the arithmetic, and the Tutor condemned his
work because he missed in it the processes which a less apt arithmetician
would have written out in full. He had become thoroughly grounded
in the elements of the Greek and Latin tongues, and was from that
time onward an accomplished classical scholar, insomuch that when,
during his Presidency at Harvard, he was obliged on one occasion to
make a Latin speech of some length, Professor Lane, to whom it was
submitted, pronounced it faultless. He held the first place in his class,
until during his Junior year he broke down from overwork, and was
obliged to leave Cambridge for a while. He always regarded his
memory as having been somewhat impaired by that illness ; but if so,
it must have previously been preternaturally capacious and retentive ;
for in after years he seemed never at a loss in recalling whatever he
had read, heard, or known, even in the minutest details. He grad-
uated the second in his class. In mathematics he had so far distin-
guished himself that Professor Peirce persistently attempted to dis-
suade him from the ministry, and to induce him to devote himself
entirely to mathematical and physical science. He had also the offer
of a high position — the directorship, if I am rightly informed — in
the National Observatory at Washington, and he was fully aware
of the distinction which he was sure to attain as a man of science ;
but the profession that he had chosen held at that early time, and
held equally to the day of his death, the supreme place in his re-
gard, as a post of duty, of privilege,, and of happiness, — a post
which he retained in part after he resigned his first pastorate, and
which it was his special joy co resume in full after an interval of
thirteen years.

While he was in college he invented an instrument for calculating
eclipses and occultations, for which he received, in 1843, the Scott
Medal of the Franklin Institute. His Commencement oration was on
" The Mathematics," and was described at the time as " the most pro-
found of the exercises of the day," and as " characterized by peculiar
soundness of thought and rare powers of reflection." He had preached
while in college, and had so far anticipated the studies of the Divinity
School that, on graduating, he entered the Middle Class. In the au-
tumn of 1845 he was invited to become pastor of the First Church in
Waltham, and was ordained for that charge on the 24th of December.
Here he passed fourteen years, which he regarded as the happiest of
his life. He won not only the confidence and warm affection of those
under his immediate charge, but a foremost place in the esteem and

THOMAS HILL. 429

honor of the whole community, even of those most widely separated
from him hy church affinities, — of Romanists as well as of Protestants.
He became an active member of the school board, the chairman for
the greater part of the time, and was largely instrumental in improving
the methods and enhancing the efficiency of the public schools. While
he regarded as chimerical, and, were it not so, as eminently undesira-
ble, the (so called) phonographic reform in printed literature, he took
the lead in utilizing the phonetic method for the earliest reading lessons
of children. Thus, by their being taught to pronounce letters as they
sound in words, the time and labor in acquiring the capacity of read-
ing were abridged by more than one half;* while even when a pho-
netic primer was used, it was found that the child in due time passed
from it to an ordinary reading-book almost without consciousness of
the change. While in this movement, revolutionary for the earliest
stage of school life, and of immeasurable value, he took the initiative,
and has been followed by the most intelligent school boards and teach-
ers, he was unrestingly active in the introduction of methods that had
been elsewhere found serviceable, and in testing experimeutarily
modes of teaching that had any just claim to careful trial. Thus
under his direction the Waltham schools became model schools, and a
centre of educational enlightenment for neighboring communities.

Meanwhile his parochial relations and intercourse were becoming
more and more intimate, and were characterized by mutual confidence
and affection, so that he was virtually a dearly beloved member of
every family in his flock. I have never known a happier pastorate
than his, one more fruitful in its best influences, or one which left on
either side more enduring and precious memories. It ought not to
have been dissolved, and had he not been too ready to yield his own
judgment to what was misrepresented to him as a matter of higher
obligation, he would probably have died the minister of Waltham.

He was repeatedly solicited to assume other charges. He was
strongly urged, under the most promising auspices, to become minister
of a church in Cincinnati. He was subsequently asked to take the
Presidency of the Meadville Theological School, but declined, in great
part, because he was unwilling to leave the regular ministry. In the
summer of 1859, he had the Presidency of Antioch College not so

* The child can perceive no reason why aitrh-o-jee should spell hog, or why
fe-you-bee should spell cub. Each separate word is acquired b}- a separate act of
memory ; while if he is taught to pronounce each letter as it sounds in the
words in which it is used, the rapid pronunciation of the letters of a word gives
him the word.

430 THOMAS HILL.

much offered to him as forced upon him. The College never had a
reason for being, and its pecuniary capital consisted largely in promises
that were never fulfilled. It had the disadvantage of being largely
supported, befriended, and reputedly managed by strong and "ood men
in New York and Boston, who were too remote from the site of the
College to detect shams and subterfuges which from the first boded
no good. Thus the man who was the earliest incumbent of the Greek
Professorship commenced the study of the Greek Reader after his
election, and had just finished it when he entered on his official duties.
But Dr. Hill's friend and kinsman (by marriage), Rev. Dr. Bellows,
not only had faith in the College, but was enthusiastic in the advocacy
of its claims. He rightly imagined that such an institution could have
ho more precious godsend than a President who was regarded as
hardly second to any as a man of science, who held so honored a
position as a minister, and who was already distinguished for his edu-
cational ability and services. He felt, and contrived to make Dr. Hill
feel, that the needs of the growing West demanded such qualifications
for the charge of higher seminaries as could be furnished only from
among trained educationists who could not accept such places without
serious sacrifice. Dr. Hill consciously made a very great sacrifice ;
but he had reason to expect at least food and clothing for himself and
his family. He was shown, not indeed actually invested capital, but
pecuniary guarantees that seemed to provide adequately for the
salaries and the running expenses of the College. These guarantees
proved to be worthless, and he was obliged to devote the time and
labor which might have been of unspeakable worth to the College to
solicitation for funds to keep the institution alive. He was so far
successful, that when he resigned his office, in the summer of 1862,
he had secured the payment of all arrears due to the members of his
Faculty, but had not reserved for himself more than ten per cent of
his own salary, having been obliged to supply the deficit in part by of-
ficiating on Sundays in a Cincinnati pulpit, at a distance of more than
seventy miles from the College. Meanwhile, his over-strong sense of
obligation made him unwilling to shorten the three years for which he
had pledged himself to serve, though within that period he might have
had a situation which, if unencumbered, he would gladly have accepted.
Among the most influential proprietors of King's Chapel were several
men who had been his summer parishioners at Waltham, and they
earnestly besought him to suffer his name to be presented for the then
vacant pastorate of the Chapel, with the assurance that there would
be a unanimous vote in his favor. But this was early in his Presi-

THOMAS HILL. 431

dency. Meauwhile his pecuniary straits were not his only trial.
There were jealousies on the part of the (so called) Christian denom-
ination, whose members, though contributing a very small portion of
the funds given or promised, claimed a large share in the adminis-
tration of the College, and possessed neither experience nor skill for
such service. On the whole, the best that could have been done, and
that only by a man of surpassing prudence, wisdom, and unselfishness,
was to come forth from this ordeal with the consciousness of leaving
the College in no worse a condition than that in which he found it,
and with abounding gratitude, respect, and honor from those associated
with him in its administration.

At the time of his resignation the Presidency of Harvard Uni-
versity was vacant, and while Dr. Hill was from the first the favorite
candidate of the late John A. Lowell, the senior and by virtue of his
experience and practical wisdom the controlling member of the Cor-
poration, the election of Dr. Hill to that office seemed to all the friends
of the College the best possible choice ; and there probably never was
a case in which the action of the governing boards was more fully
and warmly sanctioned by all whom it concerned. While he had the
respect and confidence of the entire Faculty, the scientific teachers
recognized in him their rightful head, and those in other departments
found him no less conversant with their respective lines of work than
if they had been his specialties. He already had in the board of in-
struction many friends, and there were none of the others whom he did
not make his friends, while he was singularly fortunate in the appoint-
ments voted by his recommendation. He commenced several of the
improvements in the administration which — essential to the well-
being of the College — it required the vigorous executive capacity of
his successor to sustain and carry forward, while they were still re-
garded in some influential quarters with doubt and dread. The elective
system had under him its hopeful beginnings. The Academic Council,
w hich now seems a necessity, was started at his suggestion. Previously
the several Faculties of the University, though with many common in-
terests, were without means or opportuniiy of intercommunication.
He originated the system by which they are made one body, with
officers, records, and stated times of meetings, for the discussion and
elaboration of the various measures by which they may aid one anoth-
er's efficiency, act concurrently for the benefit of the University as a
whole, and provide for the instruction and discipline of those classes of
special and graduate students that do not belong exclusively to any one
department. Under him, also, University Lectures were first opened

432 THOMAS HILL.

to the outside public, — a system which has since been so extended
that during each academic year there are a considerable number of
courses and of individual lectures in Sanders Theatre and in Sever
Hall, which, while primarily for the benefit of students, are also de-
signed and adapted for the receptivity of an intelligent audience from
the community at large. It was Dr. Hill's misfortune, that while his
heart was iu his work, and he was enabled to put into it the results of
mature experience and wisdom, he was unavoidably prevented from
giving to it the full and uninterrupted stress of vigilance and energy
which such an office demands. To the weariness of his Antioch life
was added a series of domestic afflictions, under the accumulated pres-
sure of which he was led to resign his charge in the autumn of 1868.
He then removed to Waltham, which was his home for the next four
or five years. He was for several months too much enfeebled for any
intellectual labor, but gradually recovered his strength for nearly
twenty years of full vigor of mind, and of working power more in-
tense and fruitful than at any earlier period. In the autumn of 1869
he went to California by the then newly opened Union Pacific Rail-
road, and, while he gained strength by travel, he also found access to
fields and objects of scientific and sociological interest which had not jet
become familiar to the New England mind. In 1871 he represented
the town of Waltham in the Legislature. In December of that year
he sailed with his friend Agassiz on his well known South American
expedition, and bore no small part in the explorations which have given
it a permanent place in the history of science.

Early in 1873 Dr. Hill was invited to preach in the First Church
of Portland, Maine, and immediately received an invitation to its then
vacant pastorate, which he accepted, and which he held for the re-
mainder of his life. Here he found himself in a congenial atmosphere,
with many of his stated hearers who appreciated the high intellectual
standard no less than the spiritual depth of his discourses, and in a
community comprising not a few persons of advanced culture in the
various departments in which they recognized him as a leading mind.
He made himself felt as an educationist on the school board of the city,
and the teachers enjoyed his counsel and sympathy. He was an active
member of the Portland Natural History Society, and of other local
associations scientific and literary. He became largely known in
nearer and remoter regions of his adopted State, and his services were
solicited on very numerous occasions of public interest. In Portland
he was honored, revered, and beloved by the whole community, and
hnd no more genuine admirers and warmer friends in his own church

THOMAS HILL. 433

than among the ministers and in the churches most widely separated
from him in creed and in modes of worship.

For several years Dr. Hill had delivered in the spring or early
summer a course of lectures at Meadville, before the students in the
Divinity School. In May, 1891, though but partially recovered from
serious illness, he started on a journey in which he visited friends in
Ohio, and fulfilled his Meadville engagement on his return. He
arrived at Meadville greatly enfeebled, yet could not be dissuaded
from delivering his lectures, though the effort so far exhausted him
as to make his friends very apprehensive as to his homeward journey.
On the 7th of June he reached his daughter's house in Waltham, too
ill to so farther, and for several weeks was confined almost whollv to
his bed ; and there seemed little hope that he would ever leave his
room. Here he had the assiduous and skilful care of his son in law,
Alfred Worcester, M. D., and after a few weeks the worst symptoms
nearly disappeared, and he made arrangements for returning to Port-
land to take part in the ordination of his colleague. Rev. John
C. Perkins. But on the day before that appointed for his departure
a relapse occurred, and it became certain that the end was drawing
near. After several weeks of severe suffering he died, on the 21st of
November, 1891. During this long illness he manifested in full the
strength and the sweetness of his character. His courage, patience,
and resignation indicated at once perfect self-coutrol and the power of
a religious faith which seemed hardly less than a clear vision of things
divine and eternal. He was at the same time thoughtful of the com
fort of those around him, and of whatever concerned his friends and
his official charge in Portland ; and tliere were constantly going out
from his chamber by letter and message offices of love and kindness
for an extended circle of those whom he had made his own by ties
of benefit conferred. While fully prepared to die, he was during in-
tervals of relief hopeful of continued life, that he might avail him-
self of the diminished stress of professional duty for literary labors in
behalf of the interests of science and religion, in his mind joint and
inseparable.

Dr. Hill was married in 1845 to Anne Foster Bellows, daughter of
Josiah and Mary (Sparhawk) Bellows, of Walpole, N. H., a woman
of rare beauty and loveliness of character, of superior ability and
culture, and unsurpassed in all that made her precious as a wife and
mother. She died in 1864, leaving for her husband the domestic cares
and responsibilities of which she had hardly let him feel the pressure.
In 1866 he married Lucy Elizabeth Shepard, daughter of Otis and
vol. xxvii. (n. s. xix.) 28

434 THOMAS HILL.

Ann (Pope) Shepard, of Dorchester. In this new relation there was
every promise of happiness for him and for his children; hut she early
hecame an invalid, and died in 1869.

Dr. Hill's sons are Henry Barker (H. U. 1869), Professor of Chem-
istry in Harvard University; Thomas Roby, in business in Phila-
delphia; and Otis Shepard, only child of his second marriage. Of
his four daughters three are married, respectively, to Lewis Pierce
(Bowdoin College, 1852, LL. B., H. U. 1855), of Portland, Alfred
Worcester (H. U. 1878), M. D., of Waltham, and Robert H. Monks.

Dr. Hill was, in a certain sense, unique, — the only man of his kind
that I have ever known. There was, perhaps, no department except
mathematics in which he had not his superiors, and there are men
who have covered superficially as wide a range of science and knowl-
edge as was within his scope ; but the omniscience which was said
to be Lord Brougham's foihle was his special gift. He not only
knew something in every department, but there was none within his
reach in which he was not so conversant with principles, truths, and
facts that he seemed the peer of an adept, and amply qualified to be a
teacher and guide. While as a mathematician he was well known as
second to no man of his time, there might be named several other de-
partments in either of which, had it been his specialty, he would equally
have held an unrivalled eminence.

In mathematics his earliest publication was an " Elementary Trea-
tise on Arithmetic," designed for pupils of an advanced grade, as an
introduction to Professor Peirce's series of text-books. This appeared
in 1845. In 1850 he published an " Elementary Treatise on Curva-
ture," and a " Fragmentary Essay on Curves." These works marked
the early stages of a series of investigations on curves, in which ho
performed no small amount of original work, the results of which are
somewhat densely strewn in successive records of proceedings of
scientific bodies. His attention was specially directed to the curves
of nature, those that are found in the various forms of organic life, all
of which he believed to be capable of expression by equations in the
terms of their co-ordinates, and for not a few of which he determined
the equation. In one of the papers to which we refer he described
and defined an entirely new curve to which he gave the name of the
" Tantalus."

In 1855 he published his " First Lessons in Geometry," followed
shortly afterward by a " Second Book." The first of these was de-
signed to create in the child an interest in form and figure by appeal-
ing to the imagination, and it made him acquainted by the eye with a

THOMAS HILL. 435

very considerable variety of natural curves ; while in the second,
mathematical reasoning was employed, not only for the demonstration
of elementary theorems, but for the solution of problems, some of them
such as are usually reserved for a later period of school or even college
life, but which he so simplified as to bring them within the compre-
hension of pupils of tender years. In 1849 he published " Geometry
and Faith," in which he exhibited in their close mutual relations, or
rather in their identity, the fundamental principles of mathematics and
of Christian theism. His sense of the primacy of mathematics among
the sciences found expression in his Phi Beta Kappa oration on
" Liberal Education," in 1858, and again in a course of Lowell
Lectures on " The Mutual Relation of the Sciences," in 1859. After
his removal to Portland he invented an instrument to which he gave
the name of " Nautrigon," for solving spherical triangles by construc-
tion. By its use there would have been a considerable saving of time
in nautical calculations ; but it was too expensive to come into gen-
eral use. I have already referred to his early reputation in practical
astronomy, in which he was probably as well versed as he could have
been, unless he had been directly concerned in the management of an
observatory. In physics he was not only familiar with the labors of
others, but made independent investigations of no little importance and
value. He kept even pace with chemistry in the successive stages of
its rapid progress, and would have found himself at home in a labora-
tory furnished with the latest apparatus. He was conversant with the
entire realm of organic life. In zoology he was closely associated
with Agassiz in his researches, and was constantly engaged in inde-
pendent observations of the phenomena of animal life, in which Science
was indebted to him for not a few discoveries. Botany was, next to
pure mathematics, his favorite science, to which he made frequent
contributions. He was an intimate friend of Dr. Gray, and a scien-
tific communication was forwarded in a letter to Professor Goodale but
a few weeks before his death.

I have spoken of his lifelong interest in classical literature, of which
he was, if not a close student, a critical and discriminating reader.
He was a good Hebrew scholar, and was not unacquainted with other
Semitic languages.

As to the studies specially appertaining to the clerical profession he
was among the most learned of our clergy. In the criticism of the He-
brew and Christian Scriptures he was thoroughly trained and skilled.
A course of Lowell Lectures on the " Natural Sources of Theology,"
delivered in 1870, reproduced and greatly enlarged in a series of

436 THOMAS HILL.

articles in the " Bibliotheca Sacra," formed the substance of a volume
issued in 1877, which is unsurpassed in the clearness, fulness, and
timeliness of its statement of the fundamental truths of natural re-
ligion, and in its treatment of the various current forms of scepticism.

While Dr. Hill was master of a prose style at once elegant, per-
spicuous, and strong, his genuine poetic temperament found occa-
sional expression in verse, which, although it gave him no special
distinction as a poet, showed that, had he sought a place in the upper
region of Parnassus, he could have easily won it. His two volumes
of poems are real poetry, equally in conception, diction, and rhythm,
and indicate a man of genius as their author.

He was a lover of music, and made earnest endeavors to supply the
lack of a discriminating ear. He studied thoroughly the mathematical
laws of music, the principles of harmony, and the system of musical
notation, and even made some attempts at composition. In the arts
of design he had capacity which by cultivation might have become
talent, perhaps genius. He painted landscapes in oil which were no
mean copies of nature, and was not unsuccessful in modelling portraits
in bas-relief.

As to Dr. Hill's personal character the only difficulty in portraying
it is that one knows not where to paint in the shadings. Trans-
parently frank, guileless, unsparingly faithful in duty, in all domestic
and social relations forgetful only of his own comfort and advantage,
and assuming as if rightfully his own every burden that others would
let him bear, he manifested in his whole life the beauty and power of
the religion of which he was the earnest and devoted minister. He
can have had no enemies, but more friends than can be catalogued.
Had there been in him aught of self-seeking, he would have left more
numerous and permanent records of the reputation in which he is held
by all who knew him. In the periodicals to which he was a constant
contributor, especially in the " Bibliotheca Sacra" and the " Andover
Review," are papers which, if collected and skilfully edited, would form
a series of volumes on subjects of vital interest, in which his aim was
never to draw attention to himself, but only to instruct and impress the
minds and souls of his readers. With like unselfishness of purpose,
he was always ready to give aid, at whatever cost of time and labor, to
those who were engaged in literary, scientific, or professional work,
whether for their own benefit or for publication ; and there are not a
few reputations greatly enhauced and enriched by contributions from
his own best thought and most recondite investigations. In fine, his
ruling purpose was to serve every cause of learning, virtue, and

JOSEPH LEIDY. 437

religion, and no man cared less than he, if the service were only ren-
dered, whether it was in his own name cr in that of others.

As to College honors, Dr. Hill received the degree of Doctor of
Divinity from Harvard University in I860, and that of Doctor of Laws
from Yale College in 1863. He was a member of the American Philo-
sophical Society, of the Massachusetts Historical Society, and of many
other associations of like character.

The following is a partial list of Dr. Hill's publications in other
than pamphlet form : —

Elementary Treatise on Arithmetic, 1845.

Geometry and Faith, 1849. 2d edition, revised and enlarged, 1874.

3d edition, greatly enlarged, 1882.
First Lessons in Geometry, 1855.

Jesus the Interpreter of Nature, and other Sermons, 1860.
Second Book in Geometry, 1863.

Natural Sources of Theology, reprinted from the Bibliotheca Sacra, 1874.
Arithmetic (Wentworth and Hill), 1883.
In the Woods and Elsewhere, 1888.

JOSEPH LEIDY.

Joseph Leidy, a member of this Academy since May 30, 1848,
died, after a brief illness, at his residence in Philadelphia, Pa., on
April 30, 1891. His ancestors were of French-German descent, and
came to this country as missionaries. His father, Philip Leidy, was
born in Montgomery Co., Pa., in 1791, and married Catherine Melick.

Joseph Leidy was the third child by this marriage, and was born in
Philadelphia, September 9, 1823. His mother died when he was a
year and a half old ; later his father married Christiana Melick, a sister
of his first wife. She proved to be an admirable mother to Joseph, and
to her watchful care and direction is due in great measure his choice
of life work. His early education was obtained in private schools, and
even during this period he manifested a marked inclination toward the
study of natural history, being particularly interested in plants and
minerals. After hearing a lecture on these subjects, given by an itin-
erant lecturer in the schoolhouse, young Leidy procured text-books,
and began the systematic study of botany and mineralogy. From an
early age he showed great skill in drawing. This power became so
marked that at the ajre of sixteen his father removed him from school
with the intention of having him become an artist. At this period he
spent much of his time in a wholesale drug-store near his home; here

438 JOSEPH LEIDY.

he made such good use of the opportunity for studying the nature of
various drugs, and in compounding medicines, that the proprietor
recommended the boy as being competent to take charge temporarily
of the retail drug-store of a customer.

This success led him to consider seriously the advisability of becom-
ing an apothecary. All this time he had continued his natural history
studies, and by the dissection of a few cats, chickens, etc., he devel-
oped such an interest in comparative anatomy that his step-mother de-
cided that Joseph should become neither an artist nor a druggist, hut
a physician. Having decided upon the study of medicine, he gave his
first year to the study of practical anatomy, and under the preceptor-
ship of Doctors Paul B. Goddard and James McClintock took three
full courses of medical lectures at the University of Pennsylvania, re-
ceiving in the spring of 1844 the degree of Doctor of Medicine, his
thesis being an admirable essay on " The Comparative Anatomy of the
Eye of Vertebrated Animals." He now entered upon the active prac-
tice of medicine, and at the same time was appointed Assistant to the
Chair of Chemistry in the University. He also assisted Dr. Goddard,
the Demonstrator of Anatomy.

At the end of two years he gave up the practice of medicine in order
that he might devote himself entirely to study aud teaching. His skill
in anatomy was so great that he was appointed Prosector to the Chair
of Anatomy by Professor Horner. In 1846 he was elected Demonstra-
tor of Anatomy in the Franklin Medical College, which position he held
for one year and then resigned to return to the University, where
he was again associated with Professor Horner. He also gave private
courses in anatomy. In the spring of 1848 he accompanied Dr. Hor-
ner to Europe, in the fall gave a course of lectures on Histology, and
in the following spring lectured on Physiology at the Medical In-
stitute. This constant application affected his health so that he was
obliged to abandon all work for some months. In 1850 he went abroad
with Dr. George B. Wood to make a collection of models, drawings,
etc., with which to illustrate Dr. Wood's course of lectures on Medi-
cine. This trip was of very great value to Dr. Leidy, as it enabled
him to visit all the great museums of Europe, and to make the ac-
quaintance of such distinguished anatomists and physiologists as Owen,
Majendie, Hyrtl, Johannes Muller, and others. He returned from
this trip with renewed health, and in 1851 resumed his anatomical
work at the University.

During this year he was elected a member of the College of Phy-
sicians aud appointed Pathologist to St. Joseph's Hospital. In the

JOSEPH LEIDV. 439

winter of 1852 Professor Horner through ill health was unable to con-
tinue his lectures on anatomy, and at his request Dr. Leidy was ap-
pointed as his substitute. After the death of Dr. Horner, he was, in
May, 1858, appointed Professor of Anatomy, which position he held
until his death.

During the ten years preceding his appointment to the Chair of
Anatomy, in addition to his regular duties, Dr. Leidy found time to
continue his scientific studies. In 1844, the year of his graduation, he
contributed to Amos Binney's monograph of the Mollusca an admira-
ble introductory chapter on the " Special Anatomy of the Terrestrial
Mollusks of the United States," together with sixteen beautifully
executed plates illustrating the anatomy of thirty-eight species of Mol-
lusca. In 1 845 he was elected a member of the Boston Society of Nat-
ural History, and of the Philadelphia Academy of Natural Sciences.
With the latter institution he was constantly associated during the rest
of his life, being successively Librarian, a Curator, and from 1847
chairman of the Board of Curators. With his natural mpdesty, he
many times refused the office of President, but finally in 1881 accepted
it, and remained President of the Academy to the end of his life.

The Proceedings of the Academy furnish a brilliant memorial of his
great attainments in various branches of natural science, as they con-
tain several hundred valuable contributions to zoology, paleontology,
comparative, human, and microscopic anatomy, botany, and mineralogy.
While he never regarded liimself as an authority, and published but
little upon mineralogy and botany, his knowledge of these subjects was
that of a specialist. This was well shown by the frequent verbal com-
munications which he made as Curator in calling the attention of the
Academy to additions to the mineralogical cabinet ; his knowledge of
gems and their values was also very extensive. The very fine and
valuable mineralogical collection made by him has recently been pur-
chased by the government, and will be placed in the National Museum
in Washington.

His familiarity with plants was also frequently noted at the meet-
ings of the Academy and elsewhere. The herbarium which he gave
the Biological Department of the University of Pennsylvania contains
over 1,500 species which were collected and determined by himself.

In zoology he gave especial attention to invertebrate forms ; and
while paying particular attention to parasites and Protozoa, he made
valuable contributions to our knowledge of many other groups. As
early as 1846 he observed minute specks in some pork that had been
cooked, which, when examined with a microscope, were found to be a

440 JOSEPH LEIDY.

species of Trichina. In his communication on this discovery he stated
that this species was apparently the same as that found by Owen and
himself in man. The famous zoologist Leuckart, who afterward
worked out the life history of Trichina spiralis, acknowledged his
indebtedness to this observation of Dr. Leidy. In 1853 appeared the
" Fauna and Flora within Living Animals," a beautifully illustrated
and valuable work, which showed very clearly the wide range of ani-
mal and vegetable parasites which are to be found in the alimen-
tary canals of small animals, as beetles, centipedes, cockroaches, etc.
This paper is also interesting as having expressed ideas closely re-
sembling in many respects those advanced a few years later by Darwin
in his " Origin of Species."

Dr. Leidy's contributions to helminthology were numerous, and of
such merit as to render him the highest authority on this subject in
this country, and the peer of such men as Leuckart, Cobbald, and
Diesing. His papers upon various insects and their life histories gave
evidence ^of his familiarity with entomology. In 1848 he made the
discovery of the presence of eyes in a species of Balanus, which led
Darwin to look for them in other members of this group.

Dr. Leidy was particularly interested in the very lowest forms of
animal life. In addition to many smaller papers, he gathered together
in the magnificent monograph, " Fresh Water Rhizopods of North
America," the results of many years' study. The numerous plates
illustrating this volume are splendid examples of his marvellous ar-
tistic skill. Among the first persons in this country to use the micro-
scope, he early established his ability as a histologist by his valuable
paper, " Researches into the Comparative Structure of the Liver "
(1848). The views advanced in this paper, though not generally
accepted at the time, have since been largely confirmed by embryo-
logical research.

In 1861, he published "An Elementary Text-book on Human Anat-
omy," in which the noteworthy attempt was made to substitute an
English terminology with foot-note references for the cumbersome and
perplexing anatomical nomenclature in common use. This was quite
successful, and was carried to still greater perfection in the second
edition of this book, which was finished a short time before his death.
This anatomy is unexcelled by any in the language for accuracj' of
detail and clearness of expression. Dr. Leidy's other papers upon
vertebrate anatomy exhibit the careful work and clear judgment so
characteristic of all that he did, and the many new facts presented by
him have been almost always confirmed by later investigators. No

JOSEPH LEIDY. 441

one was more ready than himself to acknowledge and correct an error
when found.

There remains still another field of scientific research in which Dr.
Leidy achieved a world-wide reputation, namely, paleontology. His
first paper on this subject appeared in 1847, "The Fossil Horse of
America." Although he was almost the first person in this country
to take up the subject of vertebrate paleontology, and had at first very
meagre opportunities for the study of the comparative osteology of
many recent forms, he produced in the next few years a series of bril-
liant papers, which entitle him to be considered as the equal of any
paleontologist produced by this country or Europe.

The following are among the more prominent of his many contri-
butions to this subject: "Ancient Fauna of Nebraska," 1853; "Me-
moir of the Extinct Sloth Tribe of North America," 1855 ; " Cretaceous
Reptiles of the United States," 1865 ; " Extinct Mammalian Fauna of
Dakota and Nebraska, together with a Synopsis of the Mammalian
Remains of North America," 1869; "Contributions to the Extinct
Vertebrate Fauna of the Western Territories," 1873; "Description of
Vertebrate Remains from the Phosphate Beds of South Carolina,"
1877.

The interest aroused by these wonderful discoveries led others
to enter this field of investigation. Great rivalry and many acrimo-
nious disputes regarding priority and nomenclature arose, so that,
rather than become entangled in controversy, Dr. Leidy gave up
this work in which he had achieved such success, and devoted him-
self to other fields of scientific work. He however contributed from
time to time small paleontological papers, the last appearing in May,
1890.

Dr. Leidy acted as surgeon to the Satterlee Military Hospital dur-
ing the war, and the results of the many interesting autopsies made by
him are recorded in the "Medical and Surgical History of the War."

He was elected a member of the National Academy of Science, in
1863, at the time of its organization. In 1871 he was appointed Pro-
fessor of Natural History in Swarthmore College; and in 1884, upon
the establishment of the Biological Department of the University of
Pennsylvania, he was appointed Professor of Zoology and Comparative
Anatomy. In 1885 he was elected President of the Wagner Free
Institute of Science in Philadelphia; and in 1889, at the time of its
organization, President of the Association of American Anatomists.

Many honors, both at home and abroad, were conferred upon this
distinguished naturalist. In 1886 Harvard University conferred upon

442

NOAH POItTKR.

him the degree of Doctor of Laws. The Boston Society of Natural
History awarded to hiin, in 1879, the Walker grand prize of $500,
which in this instance was raised to $1,000 as a special recognition of
his eontrihutions to science. In 1879 he received a prize from the
Royal Microscopical Society. The Geological Society of London
awarded to him, in 1884, the Sir Charles Lyell medal for his pale-
ontological researches ; and in 1888 he received from the Paris Acad-
emy of Sciences the Cuvier medal for his work in biology. In the
period from 1845 to 1887 he was elected honorary member by over
forty of the learned societies of Europe and this country.

It is impossible in this brief notice to do more than indicate in the
most general manner the life work of this great man, which covers
almost a half-century. In this period his eontrihutions to natural his-
tory number nearly one thousand, ranging from short papers to large
illustrated volumes, which probably contain fewer errors of fact and
interpretation than those of any other writer on so many and such
varied subjects. His personal character was in perfect accord with his
wonderful mental attainments. He was remarkable for an entire ab-
sence of self-assertion or conceit. Wholly unselfish, his amiability and
charming simplicity of manner rendered him a delightful companion,
always approachable and ready to aid a student by advice or expla-
nation. In the lecture-room his clear and concise descriptions formed
word pictures rivalling in distinctness his admirable blackboard illus-
trations. He was as incapable of deceit as he was modest, and sub-
mitted to imposition rather than enter into controversy. His long life
was devoted to science for the advancement of knowledge, and with-
out thought of gain or personal glory.

Notwithstanding failing health during the last few months, Dr.
Leidy still continued his active work ; and thus, as he desired, with
his shoulder to the wheel, one of America's greatest naturalists passed
away.

NOAH PORTER.

Noatt Porter, son of Rev. Noah Porter, D. D. (Yale College,
1803), was born in Farmington, Conn., on the 14th of December,
1811. His father was pastor of the Congregational Church in that
town for nearly sixty years, and had high reputation as a learned,
wise, faithful, and efficient minister. The son graduated at Yale Col-
lege in 1831, and immediately took charge of the Hopkins Grammar
School in New Haven, — a position which at the end of two years he

NOAH PORTER. 443

exchanged for a tutorship in College, at the same time entering the
Divinity School. He resigned the tutorship in 1835, and on complet-
ing his theological course was ordained, April 27, 1836, as pastor of
the Conjjreffational Church in New Milford, Conn. On the 13th of
the same month he married Mary Taylor, the eldest daughter of his
predecessor, and the sister of Rev. Dr. Taylor, — well known in his
time as the advocate of the more liberal type of Calvinism in the
Taylor-and-Tyler controversy, — who, as Professor of Divinity, had
been his favorite teacher, and may have borne no small part in deter-
mining the trend of his pupil's opinions.

Mr. Porter was regarded from the first as a man of superior abil-
ity, and his success in a long established church pointed to him as
eminently fitted to take charge of a church that had yet to create its
own future. He accordingly was invited to the pastorate of the then
new (South) Congregational Church of Springfield, Mass., over which
he was installed, January 12, 1843. But the friends of the College
were undoubtedly right in believing that his special fitnesses were for
academic service. He had been devoted to philosophical studies from
his college days, and had shown his teaching power and administrative
ability in his tutorship ; and when a new Professorship of Moral Phi-
losophy and Metaphysics was established, he was at once sought as its
incumbent. He was elected to this office in 1846, and filled it with
distinction, honor, aud growing influence till his death. Still retain-
ing it, though of course delegating much of its work to other hands,
he accepted the Presidency of the College on President "Woolsey's
resignation in 1871, fulfilled the difficult task of maintaining the
prestige given it by his predecessor, and retired from the chair while,
with unimpaired vigor of mind, his advanced years seemed the only
reason for so doing. He, however, was probably conscious of de-
clining bodily strength, and his last years were a period of gradual
enfeeblement, followed by an illness of several weeks, which had its
fatal issue on the 4th of March, 1892.

President Porter was a voluminous writer. Among his published
volumes are "The Human Intellect" (1868); "The American Col-
leges and the American Public" (1870); "Books and Reading"
(1871); "Elements of Intellectual Science" (1872); " Elements of
Moral Science" (1885); "Kant's Ethics" (1886); and "Fifteen
Years in the Chapel of Yale College" (1887). He also published a
large number of sermons, addresses, and articles in periodicals, espe-
cially in the New Englander, and was editor in chief of the successive
editions of Webster's Dictionary from 1860.

444 JOHN COUCH ADAMS.

His claims to distinction must have been recognized in more semi-
naries of learniug than he knew. His text-books have had, and still
have, a largely extended use in colleges and academies. The degree
of Doctor of Divinity was conferred on him by the University of New
York in 1858, and that of Doctor of Laws by Western Reserve Col-
lege in 1870, by Trinity College in 1871, and by the University
of Edinburgh in 1886. His was a not infrequent and an always
welcome presence at Harvard College, where he is gratefully re-
membered as a Phi Beta Kappa orator and as a preacher in Appleton
Chapel.

President Porter was in every respect a man of high tone, large-
hearted, broad-minded, true, sincere, faithful, honorable, making him-
self not only respected but beloved, and most by those who knew him
best. He was a firm Christian believer, with fixed opinions based on
deliberate conviction, but with only the kindest regard for those who dif-
fered from him. He cannot but have endeared himself to his students
by a gentleness which was never weak and a firmness which was never
harsh or stern. His text-books are conservative in their philosophy,
and especially valuable for the justice and candor with which he treats
the various schools and types of speculation, even when most remote
from his own. As a preacher he was always instructive and im-
pressive ; for his sermons were full of profound thought on subjects
of infinite moment, and his style, while massive and with little orna-
ment, was marked by purity of diction, clearness of meaning, and
precision of statement. In his early ministry he must have been a
popular preacher, in the better sense of the term ; of late years he
has commanded close attention and deep interest in proportion to the
receptivity of his hearers, and their own nearness to his own elevated
plane of mind, heart, and soul.

FOREIGN HONORARY MEMBERS.

JOHN COUCH ADAMS.

John Couch Adams was born at Lidcot, England, on June 5,
1819. His unusual mathematical abilities became evident early in his
life, and obtained for him the highest honors at the University of
Cambridge, where he graduated as Senior Wrangler in 1843. His
election to college fellowships made it practicable for him to devote

JOHN COUCH ADAMS. 445

himself to his favorite mathematical pursuits, and in 1858 he was made
Professor of Mathematics at the University of St.Audrews in Scotland.
He held this position only for a year, as in 1859 he was appointed to
a Cambridge Professorship, and accordingly returned to his former
residence. In 1861 he succeeded Professor Challis as Director of the
Cambridge Observatory, and continued in that office until his death,
on January 21, 1892, after a protracted illness. In 1881 , he was offered
the position of Astronomer Royal, left vacant by Airy's retirement;
but advancing years made him unwilling to accept a place requiring
so much exertion from its occupant.

The life of Adams, thus outwardly uneventful, practically consisted
of a series of mathematical researches. It may be said to have opened
with one which had the quality, rare in such work, of attracting public
attention by its dramatic character. Immediately after his graduation,
he directed his thoughts to the subject, then ripe for consideration, of
the unexplained irregularities in the movements of Uranus, and to the
question whether the place of an unknown planet, capable of producing
such perturbations, could be defined by calculation. In 1845 his
solution of the problem was communicated to Challis and to Airy,
the Directors of the Cambridge and Greenwich Observatories ; but
partly through accident, partly through the adoption of* too mechanical
methods in such search as was undertaken for the theoretical planet
in England, the discovery of the actual planet Neptune was reserved
for the continent of Europe, where Leverrier furnished the prediction
verified by Galle. The similarity of the results independently attained
by Adams and by Leverrier was such as to exclude, at least to the
uninstructed mind, the possibility that either of the investigators could
have erred in his method of inquiry ; and the remarkable nature of
their achievement won for them general admiration and applause.
The theoretical planet which they had discovered by inference certainly
differed in many important respects from the observed planet found
by Galle. Whether the approximate coincidence of the apparent
place among the stars occupied in 1846 by the theoretical and real
objects was casual or not, this certainly formed a question to be
considered only by men who felt themselves able to compete mathe-
matically with Adams ; and it has never been minutely considered by a
sufficient number of such men to establish a decision upon the subject
from which no appeal can be taken. But in the absence of a clear
decision to the contrary, the scientific world continues to regard the
predictions of Adams and Leverrier as a real mathematical discovery .;
while in any case there can be no doubt of the evidence of mental

446 GEORGE B1DDELL AIRY.

power displayed in the researches from which these predictions re-
sulted, or of their deserved prominence in the history of astronomy.

Among the various researches which were subsequently undertaken
by Adams, that relating to the secular variation of the Moon's mean
motion was perhaps the most interesting and importaut. This in-
vestigation reopened a question which had been regarded as finally
settled by Laplace. Adams detected an omission in the work of his
predecessor, which, when supplied, proved to disturb the agreement
previously supposed to exist between theory and observation. A new
physical cause was now required to explain the observed results, and
this was found in the retardation of the rotation of the Earth due to
the tides. In this case, a protracted discussion of the subject among
the foremost mathematicians who concerned themselves with astronom-
ical inquiries resulted in confirming the theory maintained by Adams.
But the amount of the secular variation forming the original subject of
discussion has not yet been definitely fixed by observation. At present
it seems probable that the researches of Adams brought theory into
better accordance with fact, instead of disturbing an existing agreement.
If this view should prevail, tidal retardation must be regarded as com-
pensated by terrestrial contraction, or by causes as yet unknown.

The orbit of the remarkable body of meteors to which is due the
recurrence of brilliant displays of shooting stars about the middle of
November, three times in each century, was another subject investi-
gated by Adams with great success. In general, it may be said that in
all the principal discussions of his time respecting recondite questions
of theoretical astronomy he took a prominent part, and that no argu-
ments were regarded with more respect than his by those capable of
appreciating them.

Besides his academical honors, he received many tokens of distinction
from learned societies, and his name was familiar, as it will long con-
tinue to be, wherever the mechanism of the solar system is discussed
or studied.

GEORGE BIDDELL AIRY.

George Biddell Airy was born at Alnwick, England, July 27,
1801. His university education was obtained at Cambridge, where his
mathematical ability became conspicuous, and where he graduated as
Senior Wrangler in 1823. In the following year he was elected a
Fellow of Trinity College ; in 1826 he was made a Professor, and in
1828 the Director of the Observatory. These early honors were

GEORGE BIDDELL AIRY. 447

abundantly justified by the number and excellence of the investigations
which he began even before his graduation, and continued during the
following years.

The results of his inquiries at this period were published in the
Transactions of the Cambridge Philosophical Society, in memoirs relat-
ing to optical and astronomical subjects. The reader of these memoirs
will not fail to observe, in addition to ingenuity and perspicuity, much
evidence that they were written from a genuiue love of inquiry, rather
than from the desire for temporary reputation. Although their sub-
jects seem at first not very closely connected, it appears that the later
inquiries were suggested by facts developed in the course of those which
preceded, and that the author was not looking for subjects on which
to write, but was impelled to write by the abundance of material which
spontaneously presented itself to his mind. As an incidental result of
the optical studies in which he was engaged, he discovered and showed
how to correct the peculiar defect of vision now so familiar to ocu-
lists under the name of astigmatism, which he found to exist in his own
left eye. Probably a considerable number of physicians and of phi-
losophers must have previously been inconvenienced in the same way
without undertaking any experiments to discover the exact nature of
the hindrance to distinct vision which existed in their cases.

Airy began work as a practical astronomer at a time when what we
now understand as practical astronomy was an art as yet, comparatively
speaking, unformed, — when much now taught in every text-book had to
be discovered or neglected by the observer in proportion to his mental
activity or indolence. Neglect was impossible to a mind so active anil
acute as Airy's ; and while his great contemporary, Bessel,was making
the way plain to future practical astronomers, Airy was finding it very
successfully for himself. He early recognized and urged the necessity
of carefully reducing all observations which are intended to contribute
substantially to our knowledge, instead of resting satisfied with the
observations themselves. Besides attending thoroughly to all the prac-
tical business connected with the management of the Cambridge Ob-
servatory, he continued the mathematical investigations which had
previously occupied him. Among these should be specially mentioned
the memoir on the inequality of long period in the motions of the
Earth and Venus, for which the Gold Medal of the Royal Astronomi-
cal Society was awarded to him in 1832.

In 1835 Airy received the appointment of Astronomer Royal, and
accordingly took charge of the Greenwich Observatory. Here he re-
mained for forty-six years, finding such abundant opport unities for the
exercise of his business abilities that his career as an investigator was

448 GEORGE BIDDELL AIRY.

practically terminated by the acceptance of his new office. New in-
struments were to be planned, and their construction superintended ;
new brauches of scientific work were to be introduced as part of the
regular business of the Observatory ; old observations were to be col-
lected, reduced, and published ; the methods of making and reducing
new observations were to be brought into systematic form; while, in
addition to these occupations, demands from other departments of the
national administration for advice and assistance in scientific matters
were frequently to receive attention from the Astronomer Royal.
Substantial progress in any science can only be made by the patient
accumulation of observed facts under the guidance of capable adminis-
trators, such as Airy. His success in this field of work had to be ac-
cepted by himself and by his friends as amends for the withdrawal of
his attention from the more strictly scientific problems which he had
shown himself so well qualified to solve.

During his administration of the Greenwich Observatory its instru-
mental equipment was entirely renewed, and in many respects greatly
enlarged ; magnetic and meteorological observation, and long after-
wards spectroscopic observation, were undertaken as parts of the pre-
scribed system of work ; the results of older and recent observations
were made accessible to the scientific public in a long series of ponder-
ous volumes, to which the astronomical investigators of this century
have constantly resorted for an important portion of the facts needed
in their studies. No enumeration of the details of Airy's work as As-
tronomer Royal will be attempted in this place ; and as an individual
student of nature little remains to be said of him, for the reasons above
stated. But his interesting experiments at the Harton Colliery, in
1854, for the determination of the density of the Earth by the obser-
vation of pendulums at the surface of the ground and at the bottom of
the mine, deserve mention in any notice of his life. In 1870 he began
an elaborate investigation into the theory of the Moon's motion, by a
new method; but, after pursuing it for many years in such time as was
at his command, he found that old age forbade him to carry it further.
He resigned his position as Astronomer Royal in 1881, and lived in
honored retirement for the ensuing ten years, dying on January 7,
1892, in consequence of an accidental fall some time before. Marrying
in 1830, he became a widower in 1875. Six children survive him.
He received the honor of knighthood in 1872, and a long series of
other complimentary distinctions at various times in his life.

Besides his original researches, he published, chiefly in his younger
days, various essays on scientific matters, distinguished by their accu-
racy and perspicuity.

WILHELM EDUARD WEBER. 449

WILHELM EDUARD WEBER.

Wilhelm Eduard Weber was born in Wittenberg, October 24,
1804. He was the second of three sons, all of whom became eminent.
He was early interested in scientific pursuits, and while yet a student
he investigated the phenomena of waves, and with his brother Ernst
published a treatise on the subject which has ever since been consid-
ered a classic on wave motions. One of the discoveries first made
known here was that the particles on the surface of a liquid when
there is an advancing wave, all revolve in vertical circles in the plane
of the direction of propagation of the wave, while the particles lower
down move in ellipses whose vertical axis becomes smaller and smaller
as the particles are deeper. This work was issued in 1825, when
Weber was but twenty-one years of age. In 1826 he took his doc-
tor's degree at the University of Halle, and was then appointed Privat-
doceut. and Professor Extraordinary of Physics in 1828.

In 1831 he was called to Gottingen to succeed J. T. Mayer in
the Chair of Physics. Here, he with his brother Eduard investi-
gated the mechanism of walking, and this resulted in a treatise on
the subject in 1833. This too was a work of high rank. He also
published several important papers on acoustics. It will be remem-
bered that it was in these years that Faraday had entered upon his
work as a discoverer in electricity and magnetism, and during which
he had made known the mechanical relations between magnetism and
electricity, and led the way to many devices for utilizing magneto-
electric currents. Weber and Gauss were among the first to apply
the newly discovered properties to the purposes of telegraphy, and in
1833 they constructed a telegraph connecting the Physical Laboratory
of the University with its Observatory, a distance of about three-
quarters of a mile. The first use of their devices was to compare the
clocks at the two stations, but the line was also used for telegraphic
purposes proper. At first only about two letters per minute could be
transmitted ; nevertheless, in Germany these two are still considered
to be the inventors of telegraphy.

■ In 1837 a new King began his reign in Hanover. His notions of
his prerogatives were such that he suspended the constitution, and
this called forth vigorous protests from several of the professors at
the University, Weber among them. To punish them, seven Pro-
fessors were dismissed from their chairs, and three were even ban-
ished from the country. Weber was thus forced into retirement
for some years. In 1843 he was invited to the Chair of Physics
vol. xxvii. (s. s. xix.) 29

450 WILHELM EDUARD WEBER.

at Leipzig, but he returned to his former position in Gottiugen in
1849.

The chief contributions to science, those for which he is now best
known, and will long continue to be known, are, first, a series of papers
beginning in 1846, and continued at intervals to 1864, in which he
for the first time showed how the principles of absolute measurement
which Gauss had applied to magnetism were applicable to electricity.
Until Weber's work there had been no such thing as electrical
measurements. There had been nothing more than comparisons
between magnitudes of the same kind. Weber showed how an elec-
trical quantity could be stated in terms of the unit of time, length,
and mass, without any reference to other electrical phenomena, and
this was a new and great achievement. The British Association Com-
mittee on Electrical Standards adopted Weber's work as a basis for
their standards of units.

Secondly, he was one of the first to feel the necessity for an adequate
mechanical conception of electro-magnetic phenomena, and he worked
out in a mathematical way, and gave consistency to the idea of mo-
lecular magnets, that is, that every molecule of iron is a magnet by
constitution, and the various phenomena of the magnetic field are due
to the relative positions of these molecules. It hardly needs to be
said, that all the known phenomena of magnets, up to date, tend to
corroborate and strengthen that conception.

He was an honorary member of many of the learned societies of
Europe, as well as of the American Academy.

He died on June 23, 1891, and was therefore eighty-seven years
of age.

The names of five persons have been dropped from the list
of Resident Fellows on account of removal from the Com-
monwealth or non-payment of assessments.

The Academy has received an accession of ten Resident
Fellows, and two Associate Fellows.

The Roll of the Academy, corrected to date, includes the
names of 176 Fellows, 87 Associate Fellows, and 65 Foreign
Honorary Members.

May 24, 1892.

LIST

OF THE

FELLOWS AND FOREIGN HONORARY MEMBERS.

(Corrected to March, 1893.)

RESIDENT FELLOWS. — 191.

(Number limited to two liundreil.)

Class I. — Mathematical and Physical Sciences. — 70.

Section I. — 7.

Mathematics.

Benj. A. Gould, Cambridge.

Gustavus Hay, Boston.

Benjamin O. Peirce, Cambridge.

John D. Runkle, Brookline.

T. H. Safford, Williamstown.

William E. Story, Worcester.

Henry Taber, Worcester.

Section II. — 10.

Practical Astronomy and Geodesy.

Solon I. Bailey, Cambridge.

Seth C. Chandler, Cambridge.

Alvan G. Clark, Cambridgeport
J. Rayner Edmands, Cambridge.
Henry Mitchell, Boston.

Edward C. Pickering, Cambridge.
John Ritchie, Jr., Boston.
Edwin F. Sawyer, Brighton.
Arthur Searle, Cambridge.

O. C. Wendell, Cambridge.

Section III. — 41.
Physics and Chemistry.

A. Graham Bell,
Clarence J. Blake,
Francis Blake,
John H. Blake,
Arthur M. Comey,
Josiah P. Cooke,
Charles R. Cross,
Amos E. Dolbear,
Thos. M. Drown,
Charles W. Eliot,
Moses G. Farmer,
Thomas Gaffield,
Wolcott Gibbs,
Edwin H. Hall,
Henry B. Hill,
Silas W. Holman,
William L. Hooper,
Henry M. Howe,
Charles L. Jackson,
William W. Jacques,
Alonzo S. Kimball,
Leonard P. Kinnicutt,

Washington .

Boston.

Weston.

•

Boston.
Somerville.
Cambridge.
Boston.
Somerville.
Boston.
Cambridge.
Eliot, Me.
Boston.
Newport, R. I.
Cambridge.
Cambridge.
Boston.
Somerville.
Boston.
Cambridge.
Newton.
Worcester.
Worcester.

452

RESIDENT FELLOWS.

Worcester.

Worcester.

Washington.

Chicago, 111.

Newton.

Boston.

William R. Livermore, Boston.
Charles F. Mabery, Cleveland.
A. A. Michelson,
George D. Moore,
Charles E. Munroe,
John U. Nef,
Lewis M. Norton,
Robert 11. Richards,
Theodore W. Richards, Cambridge.
Edward S. Ritchie, Newton.
A. Lawrence Rotch, Boston.
Charles R. Sanger, Cambridge.
Stephen P. Sharpies, Cambridge.
Francis H. Storer, Boston.
Elihu Thomson, Lynn.

John Trowbridge, Cambridge.

Cambridge.

Harold Whiting,

Charles H. Wing,
Edward S. Wood,

Ledger, N. C.
Cambridge.

Section IV. — 12.
Technology and Engineering.

Eliot C. Clarke,
Gaetano Lanza,
E. D. Leavitt,
Hiram F. Mills,
Cecil H. Peabody,
Alfred P. Rockwell,
Andrew H. Russell,
Peter Schwamb,
Charles S. Storrow,
George F. Swain,
William Watson,
Morrill Wyman,

Boston.
Boston.
Cambridgeport.
Lawrence.
Boston.
Boston.
Boston.
Arlington.
Boston.
Boston.
Boston.
Cambridge.

Class II. — Natural and Physiological Sciences. — 57.

Section I. — 9.

Geology, Mineralogy, and Physics of
the Globe.

Thomas T. Bouve,
Algernon Coolidge,
William O. Crosby,
William M. Davis,
O. W. Huntington,
Jules Marcou,
William II. Niles,
Nathaniel S. Shaler,
Warren Upham,

Section II.

Botany.

William G. Farlow,
Charles E. Faxon,
George L. Goodale,
H. H. Hunnewell,
Benj. L. Robinson,
Charles S. Sargent,
Arthur B. Seymour,
Charles J. Sprague,
Roland Thaxter,

Boston.

Boston.

Boston.

Cambridge.

Cambridge.

Cambridge.

Cambridge.

Cambridge.

Somerville.

— 9.

Cambridge.

Boston.

Cambridge.

Wellesley.

Cambridge.

Brookline.

Cambridge.

Boston.

Cambridge.

Section III. — 20.

Zoology and Physiology.

Alex. E. R. Agassiz,
Robert Amory,
James M. Barnard,
Henry P. Bowditch,
Wm. Brewster,
Louis Cabot,
Harold C. Ernst,
J. Walter Fewkes,
Edw. G. Gardiner,
Samuel Henshaw,
Alpheus Hyatt,
Theodore Lyman,
Edward L. Mark,
Charles S. Minot,
Edward S. Morse,
James J. Putnam,
Samuel H. Scudder,
William T. Sedgwick,
Henry Wheatland,
James C. White,

Cambridge.

Boston.

Milton.

Boston.

Cambridge.

Brookline.

Boston.

Boston.

Boston.

Cambridge.

Cambridge.

Brookline.

Cambridge.

Boston.

Salem.

Boston.

Cambridge.

Boston.

Salem.

Boston.

RESIDENT FELLOWS.

453

Section IV. — 19.

Medicine and Surgery.

Samuel L. Abbot, Boston.
Edward H. Bradford, Boston.
Arthur T. Cabot, Boston.

David W. Cheever, Boston.
Benjamin E. Cotting, Roxbury.
Frank W. Draper, Boston.
Thomas D wight, Boston.

Reginald H. Fitz, Boston.

Charles F. Folsom,
Richard M. Hodges,
Oliver W. Holmes,
Frederick I. Knight,
Francis Minot,
Samuel J. Mixter,
Wm. L. Richardson,
George C. Shattuck,
Henry P. Walcott,
John C. Warren,
Henry W. Williams,

Boston.

Boston.

Boston.

Boston.

Boston.

Boston.

Boston.

Boston.

Cambridge.

Boston.

Boston.

Class III. — Moral and Political Sciences. — 64.

Section I. — 10.
Philosophy and Jurisprudence.

James B. Ames,
Charles C. Everett,
Horace Gray,
John C. Gray,
Nathaniel Holmes,
John E. Hudson,
John Lowell,
Henry W. Paine,
Josiah Royce,
James B. Thayer,

Cambridge.

Cambridge.

Boston.

Boston.

Cambridge.

Boston.

Newton.

Cambridge.

Cambridge.

Cambridge.

Section n. — 19.

Philology and Archaeology.

William S. Appleton, Boston.
Charles P. Bowditch, Boston.
Lucien Carr, Cambridge.

Franklin Carter,
Joseph T. Clarke,
Henry G. Denny,
Epes S. Dixwell,
William Everett,
William W. Goodwin, Cambridge
Henry W. Haynes, Boston.
Bennett H. Nash, Boston.
Frederick W. Putnam, Cambridge
Edward Robinson, Boston.
F. B. Stephenson, Boston.

Williamstown.
Boston.
Boston.
Cambridge.
Quincy.

Joseph H. Thayer, Cambridge.
Crawford H. Toy,
John W. White,
Justin Wiusor,
Edward J. Young,

Cambridge.
Cambridge.
Cambridge.
Waltham.

Section IIL — 23.

Political Economy and History

Charles F. Adams, Quincy.

Edward Atkinson, Boston.

Edmund H. Bennett, Boston.

Mellen Chamberlain. Chelsea.

John Cummings,

Andrew M. Davis,

Charles F. Dunbar,

Samuel Eliot,

Ephraim Emerton,

A. C. Goodell, Jr.,

Henry C. Lodge,

Augustus Lowell,

Edward J. Lowell,

Silas M. Macvane,

Francis Parkman,

Woburn.

Cambridge.

Cambridge.

Boston.

Cambridge.

Salem.

Boston.

Boston.

Boston.

Cambridge.

Boston.

Andrew P. Peabody, Cambridge.

John C. Ropes,

Denman W. Ross,

Charies C. Smith,

F. W. Taussig,

Henry W. Torrey,

Francis A. Walker,

Robert C. Winthrop, Boston.

Boston .

Cambridge .

Boston.

Cambridge.

Cambridge.

Boston.

454

RESIDENT FELLOWS.

Section IV. — 12.

Literature and the Fine Arts.

Francis Bartlett, Boston.

John Bartlett, Cambridge.

George S. Boutwell, Groton.

Martin Brimmer, Boston.

J. Elliot Cabot,
Francis J. Child,
Thos. W. Higginson,
Charles G. Loring,
Percival Lowell,
Charles Eliot Norton,
Horace E. Scudder,
Barrett Wendell,

Brookline.

Cambridge.

Cambridge.

Boston.

Brookline.

Cambridge.

Cambridge.

Boston.

ASSOCIATE FELLOWS.

455

ASSOCIATE FELLOWS. — 96.

(Number limited to one hundred.)

Class I. — Mathematical and Physical Sciences. — 36.

Section I. — 6.

Mathematics.

Fabian Franklin, Baltimore.
Emory McClintock, New York.
Simon Newcomb, Washington.
H. A. Newton, New Haven.
James E. Oliver, Ithaca, N.Y.
J. N. Stockwell, Cleveland, Ohio.

Section II. — 14.

Practical Astronomy and Geodesy.
Edward E. Barnard, San Jose. Cal.
W. H.C. Bartlett, Yonkers, N.Y.
S. W. Burnham, Chicago.

San Francisco.

Geo. Davidson,

Wm. H. Emory,

Asaph Hall,

George W. Hill,

E. S. Holden,

James E. Keeler,

Sam. P. Langley, Washington.

T. C. Mendenhall, Washington.

William A. Rogers, Waterville, Me.

George M. Searle, Washington.

Chas. A. Young, Princeton, N.J.

Washington.
Washington.
Washington.
San Jose, Cal.
Allegany, Pa.

Section III. — 11.

Physics and Chemistry.

Carl Barus, Washington.

J. Willard Gibbs, New Haven.
Frank A. Gooch, New Haven.
S.W.Johnson, New Haven.
M. C. Lea, Philadelphia.

J. W. Mallet, Charlottesville, Ya.
A. M. Mayer, Hoboken, N. J.
Edward W. Morley, Cleveland, O.
Ira Remsen, Baltimore.

Ogden N. Rood, New York.
H. A. Rowland, Baltimore.

Section IV. — 5.
Technology and Engineering.

Henry L. Abbot, New York.
Cyrus B. Comstock, Washington.
Geo. S. Morison, New York.
John Newton, New York.

William Sellers, Philadelphia.

Class II. — Natural and Physiological Sciences. — 31.

Section I. — 11.

Geology, Mineralogy, and Physics of
the Globe.

Cleveland Abbe,
George J. Brush,
James D. Dana,
Sir J.W. Dawson,
F. A. Genth,

Washington.
New Haven.
New Haven.
Montreal.
Philadelphia.

James Hall, Albany, N.Y.

F. S. Holmes, Charleston, S.C.
Clarence King, New York.
Joseph Le Conte, Berkeley, Cal.
J. Peter Lesley, Philadelphia.
J. W. Powell, Washington.
R. Pumpelly, Newport, R.I.
Alfred R. C. Selwyn, Ottawa.
Geo. C. Swallow, Columbia, Mo.

456

ASSOCIATE FELLOWS.

Section II. — 4.

Botany.

A. W. Chapman, Apalachicola, Fla.
D. C. Eaton, New Haven.

Wm. Trelease, St. Louis.
George Vasey, Washington.

Section III. — 8.

Zoology and Physiology.

Joel A. Allen, New York.

Wm. K. Brooks, Baltimore.
George B. Goode, Washington.

O. C. Marsh,
H. N. Martin,
S. Weir Mitchell,
A. S. Packard,

New Haven.
Baltimore.
Philadelphia.
Providence.

A. E. Verrill, New Haven.

Section IV. — 5.

Medicine and Surgery.
John S. Billings, Washington.
Jacoh M. Da Costa, Philadelphia.
W. A. Hammond, New York.
Alfred Stille, Philadelphia.

H. C. Wood, Philadelphia.

Class III. — Moral and Political Sciences. — 29.

Section I. — 8.

Philosophy and

T. M. Cooley,

D. R. Goodwin,
A. G. Haygood,
James McCosh,
Charles S. Peirce,
Thos. R. Pynchon

E. G. Robinson,
Jeremiah Smith,

Jurisprudence.
Ann Arbor, Mich.
Philadelphia.
Oxford, Ga.
Princeton, N.J.
New York.
, Hartford, Conn.
Providence.
Dover, N. H.

Section II. — 7.

Philology and

A. N. Arnold,
Timothy Dwight,

D. C. Gilman,
A. C. Kendrick,

E. E. Salisbury,
A. D. White,
W. D. Whitney,

Archaeology.

Pawtuxet, R.I.
New Haven.
Baltimore.
Rochester, N.Y.
New Haven.
Ithaca, N.Y.
New Haven.

Section III. — 8.
Political Economy and History.

Henry Adams,
Geo. P. Fisher,
M. F. Force,
Henry C. Lea,
Edward J. Phelps,
W. G. Sumner,
J. H. Trumbull,
David A. Wells,

Washington.
New Haven.
Cincinnati.
Philadelphia.
Burlington, Vt.
New Haven.
Hartford, Conn.
Norwich, Conn.

Section IV. — 6.

Literature and the Fine Arts.
James B. Angcll, Ann Arbor, Mich.
L. P. di Cesnola, New York.
F. E. Church, New York.

R. S. Greenough, Florence.
William W. Story, Rome.
Wm. R. Ware, New York.

FOREIGN HONORARY MEMBERS.

457

FOREIGN HONORARY MEMBERS.

69.

(Elected as vacancies occur.)

Class I. — Mathematical and Physical Sciences. — 24.

Section I.

— 5.

Section III

— 11.

Mathematics.

Physics and Chemistry.

Francesco Briosclii,
Arthur Cayley,
Hugo Gylde'n,
Charles Hermite,
J. J. Sylvester,

Milan.

Cambridge.

Stockholm.

Paris.

Oxford.

Adolf Baeyer,

Marcellin Berthelot,

R. Bunsen,

H. L. F. Helmholtz,

Mendeleeff,

Munich.
Paris.

Heidelberg.
Berlin.
5t. Petersburg

Victor Meyer,

Heidelberg.

Marignac,

Geneva.

Lord Rayleigh,

Witham.

Section II

— 6.

Sir H. E. Roscoe,
Sir G. G. Stokes,

London.
Cambridge.

Practical Astronomy

and Geodesy.

Julius Thomsen,

Copenhagen.

Arthur Auwers,

Berlin.

J. H. W. Dollen,
H. A. E. A. Faye,

Pulkowa.
Paris.

Section IV

. o

William Huggins,
Otto Struve,

London.
Pulkowa.

Technology and Engineering.

H. C. Vogel,

Potsdam.

Lord Kelvin,

Glasgow.

F. M. de Lesseps,

Paris.

Class II. — Natural and Physiological Sciences. — 25.

Section I. — 6.

Geology, Mineralogy, and Physics of
the Globe.

H. Ernst Beyrich, Berlin.
Alfred Des Cloizeaux, Paris.
A. E. Nordenskiold, Stockholm.
C F. Rammelsberg, Berlin.
Henry C. Sorby, Sheffield.

Heinrich Wild, St. Petersburg.

Section II. — 7.

Botany.

J. G. Agardh, Lund.

AlphonsedeCandolle, Geneva.

Sir Joseph D. Hooker, London.

Baron von Mueller, Melbourne.

Julius Sachs, Wiirzburg.

Marquis de Saporta, Aix.

Eduard Strasburger, Bonn.

458

FOREIGN HONORARY MEMBERS.

Section III. — 9.

Zoology and Physiology.

P. J. Van Beneden, Louvain.

Du Bois-Reymoud, Berlin.

Thomas H. Huxley, London.

Albrecht Kolliker, Wiirzburg.

Lacaze-Duthiers, Paris.

Rudolph Leuckart, Leipsic.

C. F. W. Ludwig, Leipsic.

Louis Pasteur, Paris,

J. J. S. Steenstrup, Copenhagen

Section IV. — 3.

Medicine and Surgery.

C. E. Brown-Sequard, Paris.
Sir James Paget, London.

Rudolph Virchow, Berlin.

Class III. — Moral and Political Sciences. — 20.

Section I. — 3.

Philosophy and Jurisprudence.

James Martineau, London.

Henry Sidgwick, Cambridge.

Sir James F. Stephen, London.

Section II. — 7.
Philology and Archaiology.

Sir John Evans, Hemel Hempstead.
Pascual de Gayangos, Madrid.
Benjamin Jowett, Oxford.
J. W. A. Kirchhoff, Berlin.
G. C. C. Maspero, Paris.
Max Miiller, Oxford.

Sir H. C. Rawliuson, London.

Section III. — 7.

Political Economy and History.

Due de Broglie, Paris.

Ernst Cm-tius, Berlin.

W. Ewart Gladstone, Hawarden.

Charles Merivale, Ely.

Theodor Mommsen, Berlin.

Jules Simon, Paris.

Wm. Stubbs, Oxford.

Section IV. — 3.

Literature and the Fine Arts.

Jean Le'on Gerome, Paris.
John Ruskin, Coniston.

Leslie Stephen, London.

STATUTES AND STANDING VOTES.

STATUTES.

(Adopted May 30, 1854 : amended September 8, 1857, November 12, 1862,
May 24, 1864, November 9, 1870, May 27, 1873, January 26, 1876,
June 16, 1886, October 8, 1890, and January 11, 1893.)

CHAPTER I.

Of Fellows and Foreign Honorary Members.

1. The Academy consists of Felloivs and Foreign Honorary Mem-
bers. They are arranged in three Classes, according to the Arts and
Sciences in which they are severally proficient, viz. : Class I. The
Mathematical and Physical Sciences; — Class II. The Natural and
Physiological Sciences; — Class III. The Moral and Political Sci-
ences. Each Class is divided into four Sections, viz. : Class I.,
Section 1. Mathematics ; — Section 2. Practical Astronomy and
Geodesy; — Section 3. Physics and Chemistry; — Section 4. Tech-
nology and Engineering. Class II., Section 1. Geology, Miner-
alogy, and Physics of the Globe; — Section 2. Botany; — Section
3. Zoology and Physiology; — Section 4. Medicine and Surgery.
Class III., Section 1. Philosophy and Jurisprudence; — Section
2. Philology and Archaeology; — Section 3. Political Economy and
History ; — Section 4. Literature and the Fine Arts.

2. Fellows, resident in the State of Massachusetts, only, may
vote at the meetings of the Academy.* Each Resident Fellow
shall pay an admission fee of ten dollars and such annual assess-
ment, not exceeding ten dollars, as shall be voted by the Academy
at each annual meeting.

* The number of Resident Fellows is limited by the Charter to 200.

4G0 STATUTES OP THE AMERICAN ACADEMY

3. Fellows residing out of the State of Massachusetts shall be
known and distinguished as Associate Fellows. They shall not
be liable to the payment of any fees or annual dues, but on remov-
ing within the State shall be admitted to the privileges,* and be
subject to the obligations, of Resident Fellows. The number of
Associate Fellows shall not exceed one hundred, of whom there
shall not be more than forty in either of the three Classes of the
Academy.

4. The number of Foreign Honorary Members shall not exceed
seventy-five / and they shall be chosen from among persons most
eminent in foreign countries for their discoveries and attainments
in either of the three departments of knowledge above enumerated.
And there shall not be more than thirty Foreign Members in either
of these departments.

CHAPTER II.

Of Officers.

1. There shall be a President, a Vice-President, a Corresponding
Secretary, a Recording Secretary, a Treasurer, and a Librarian,
which officers shall be annually elected, by written votes, at the
Annual Meeting, on the day next preceding the last Wednesday
in May.

2. At the same time, and in the same manner, nine Councillors
shall be elected, three from each Class of the Academy, but the
same Fellows shall not be eligible on more than three successive
years. These nine Councillors, with the President, Vice-President,
the two Secretaries, the Treasurer, and the Librarian, shall con-
stitute the Council. It shall be the duty of this Council to exercise
a discreet supervision over all nominations and elections. With
the consent of the Fellow interested, they shall have power to make
transfers between the several Sections of the same Class, reporting
their action to the Academy.

3. If any office shall become vacant during the year, the va-
cancy shall be filled by a new election, and at the next stated
meeting.

* Associate Fellows may attend, but cannot vote, at meetings of the Acad-
emy. See Chapter I., 2.

OF -ARTS AND SCIENCES. 4G1

CHAPTER III.

Op the President.

1. It shall be the duty of the President, and, in his absence, of
the Vice-President, or next officer in order as above enumerated, to
] 'reside at the meetings of the Academy; to summon extraordinary
meetings, upon any urgent occasion; and to execute or see to the
execution of the Statutes of the Academy.

2. The President, or, in his absence, the next officer as above
enumerated, is empowered to draw upon the Treasurer for such
sums of money as the Academy shall direct. Bills presented on
account of the Library, or the Publications of the Academy, must
be previously approved by the respective committees on these
departments.

3. The President, or, in his absence, the next officer as above
enumerated, shall nominate members to serve on the different com-
mittees of the Academy which are not chosen by ballot.

4. Any deed or writing to which the common seal is to be
affixed shall be signed and sealed by the President, when thereto
authorized by the Academy.

CHAPTER IV.

Of Standing Committees.

1. At the Annual Meeting there shall be chosen the following
Standing Committees, to serve for the year ensuing, viz. : —

2. The Committee of Finance, to consist of the President, Treas-
urer, and one Fellow chosen b}r ballot, who shall have charge of the
investment and management of the funds and trusts of the Acad-
emy. The general appropriations for the expenditures of the
Academy shall be moved by this Committee at the Annual Meet-
ing, and all special appropriations from the general and publication
funds shall be referred to or proposed by this Committee.

3. The Ptumford Committee, of seven Fellows, to be chosen by
ballot, who shall consider and report on all applications and claims
for the Rumford Premium, also on all appropriations from the in-
come of the Rumford Fund, and generally see to the due and proper
execution of this trust.

4. The Committee of Publication, of three Fellows, to whom all

462 STATUTES OF THE AMERICAN ACADEMY

memoirs submitted to the Academy shall be referred, and to whom
the printing of memoirs accepted for jmblication shall be intrusted.

5. Tbe Committee on the Library, of three Fellows, who shall
examine the Library, and make an annual report on its condition
and management.

6. An Auditing Committee, of two Fellows, for auditing the
accounts of the Treasurer.

CHAPTER Y.

Of the Secretaries.

1. The Corresponding Secretary shall conduct the correspond-
ence of the Academy, recording or making an entry of all letters
written in its name, and preserving on file all letters which are
received; and at each meeting he shall present the letters which
have been addressed to the Academy since tbe last meeting. With
the advice and consent of the President, he may effect exchanges
with other scientific associations, and also distribute copies of the
publications of the Academy among the Associate Fellows and For-
eign Honorary Members, as shall be deemed expedient; making
a report of his proceedings at the Annual Meeting. Under the
direction of the Council for Nomination, he shall keep a list of
the Fellows, Associate Fellows, and Foreign Honorary Members,
arranged in their Classes and in Sections in respect to the special
sciences in which they are severally proficient; and he shall act
as secretary to the Council.

2. The Recording Secretary shall have charge of the Charter
and Statute-book, journals, and all literary papers belonging to the
Academy. He shall record the proceedings of the Academy at its
meetings; and after each meeting is duly opened, he shall read the
record of the preceding meeting. He shall notify the meetings of
the Academy, and apprise committees of their appointment. He
shall post up in the Hall a list of the persons nominated for elec-
tion into the Academy; and when any individual is chosen, he
shall insert in the record the names of the Fellows by whom he
was nominated.

3. The two Secretaries, with the Chairman of the Committee of
Publication, shall have authority to publish such of the proceedings
of the Academy as may seem to them calculated to promote the
interests of science.

OP A.RTS AND SCIENCES. 463

CHAPTER VI.

Of the Treasurer.

1. The Treasurer shall give such security for the trust reposed
in him as the Academy shall require.

2. He shall receive officially all moneys due or payable, and all
bequests or donations made to the Academy, and by order of the
President or presiding officer shall pay such sums as the Academy
may direct. He shall keep an account of all receipts and expendi-
tures; shall submit his accounts to the Auditing Committee; and
shall report the same at the expiration of his term of office.

3. The Treasurer shall keep a separate account of the income
and appropriation of the Rumford Fund, and report the same
an n nail y.

4. All moneys which there shall not be present occasion to
expend shall be invested by the Treasurer, under the direction of
the Finance Committee, on such securities as the Academy shall
direct.

CHAPTER VII.
Of the Librarian and Library.

1. It shall be the duty of the Librarian to take charge of the
books, to keep a correct catalogue of the same, and to provide for
the delivery of books from the Library. He shall also have the
custody of the publications of the Academy.

2. The Librarian, in conjunction with the Committee on the
Library, shall have authority to expend, as they may deem ex-
pedient, such sums as may be appropriated, either from the Rum-
ford or the General Fund of the Academy, for the purchase of
books, and for defraying other necessary expenses connected with
the Library. The}* shall have authority to propose rules and regu-
lations concerning the circulation, return, and safe-keeping of
books ; and to appoint such agents for these purposes as they may
tli ink necessary.

3. To all books in the Libraiy procured from the income of the
Rumford Fund, the Librarian shall cause a stamp or label to be
affixed, expressing the fact that they were so procured.

404 STATUTES OF THE AMERICAN ACADEMY

4. Every person who takes a book from the Library shall give a
receipt for the same to the Librarian or his assistant.

5. Every book shall be returned in good order, regard being had
to the necessary wear of the book with good usage. And if any
book shall be lost or injured, the person to whom it stands charged
shall replace it by a new volume or set, if it belongs to a set, or
pay the current price of the volume or set to the Librarian ; and
thereupon the remainder of the set, if the volume belonged to a set,
shall be delivered to the person so paying for the same.

6. All books shall be returned to the Library for examination,
at least one week before the Annual Meeting.

CHAPTER VIII.

Op Meetings.

1. There shall be annually four stated meetings of the Acad-
emy; namely, on the second Wednesday in May (the Annual
Meeting), on the second Wednesday in October, on the second
Wednesday in January, and on the second Wednesday in March ;
to be held in the Hall of the Academy, in Boston. At these meet-
ings only, or at meetings adjourned from these and regularly
notified, shall appnrpriations of money be made, or alterations of
the statutes or standing votes of the Academy be effected.

2. Fifteen Fellows shall constitute a quorum for the transaction
of business at a stated meeting. Seven Fellows shall be sufficient to
constitute a meeting for scientific communications and discussions.

3. The Recording Secretary shall notify the meetings of the
Academy to each Fellow residing in Boston and the vicinity; and
he may cause the meetings to be advertised, whenever he deems
such further notice to be needful.

CHAPTER IX.

Of the Election of Fellows and Honorary Members.

1. Elections shall be made by ballot, and only at stated
meetings.

2. Candidates for election as Resident Fellows must be proposed
by two or more Resident Fellows, in a recommendation signed by

OF ARTS AND SCIENCES. 465

them, specifying the Section to which the nomination is made,
which recommendation shall be transmitted to the Corresponding
Secretary, and by him referred to the Council for Nomination. No
person recommended shall be reported by the Council as a candi-
date for election, unless he shall have received a written approval,
signed at a meeting of the Council by at least eight of its members.
All nominations thus approved shall be read to the Academy at a
stated meeting, and shall then stand on the nomination list during
the interval between two stated meetings, and until the balloting.
No person shall be elected a Resident Fellow, unless he shall have
been resident in this Commonwealth one year next preceding his
election; and any Resident Fellow who shall remove his domicile
from the Commonwealth, shall be deemed to have abandoned his
Fellowship. If any person elected a Resident Fellow shall neglect
for one year to pay his admission fee, his election shall be void;
and, if any Resident Fellow shall neglect to pay his annual assess-
ments for two years, provided that his attention shall have been
called to this article, he shall be deemed to have abandoned his
Fellowship; but it shall be in the power of the Treasurer, with the
consent of the Council, to dispense (sub silentio) with the payment
both of the admission fee and of the assessments, whenever in any
special instance he shall think it advisable so to do.

3. The nomination of Associate Fellows shall take place in the
manner prescribed in reference to Resident Fellows; and after such
nomination shall have been publicly read at a stated meeting pre-
vious to that when the balloting takes place, it shall be referred to
a Council for Nomination; and a written approval, authorized and
signed at a meeting of said Council by at least seven of its mem-
bers, shall be requisite to entitle the candidate to be balloted for.
The Council may in like manner originate nominations of Associate
Fellows, which must be read at a stated meeting previous to the
election, and be exposed on the nomination list during the interval.

4. Foreign Honorary Members shall be chosen only after a
nomination made at a meeting of the Council, signed at the time
by at least seven of its members, and read at a stated meeting pre-
vious to that on which the balloting takes place.

5. Three fourths of the ballots cast must be affirmative, and the
number of affirmative ballots must amount to eleven to effect an
election of Fellows or Foreign Honorary Members.

G. Each section of the Academy is empowered to present lists of
persons deemed best qualified to fill vacancies occurring in the

VOL. XXVII. (n. s. xix.) 30

466 STATUTES OP THE AMERICAN ACADEMY

number of Foreign Honorary Members or Associate Fellows allotted
to it; and such lists, after being read at a stated meeting, shall
be referred to the Council for Nomination.

7. If, in the opinion of a majority of the entire Council, any
Fellow — Resident or Associate — shall have rendered himself un-
worthy of a place in the Academy, the Council shall recommend to
the Academy the termination of his Fellowship; and, provided that
a majority of two thirds of the Fellows at a stated meeting, consist-
ing of not less than fifty Fellows, shall adopt this recommendation,
his name shall be stricken off the roll of Fellows.

CHAPTER X.

Op Amendments op the Statutes.

1. All proposed alterations of the Statutes, or additions to them,
shall be referred to a committee, and, on their report at a subse-
quent meeting, shall require for enactment a majority of two thirds
of the members present, and at least eighteen affirmative votes.

2. Standing Votes may be passed, amended, or rescinded, at any
stated meeting, by a majority of two thirds of the members present.
They may be suspended by a unanimous vote.

CHAPTER XI.

Op Literary Performances.

1. The Academy will not express its judgment on literary or
scientific memoirs or performances submitted to it, or included in
its publications.

OF ARTS AND SCIENCES. 467

STANDING VOTES.

1. Communications of which notice has heen given to the Secre-
tary shall take precedence of those not so notified.

2. Eesident Fellows who have paid all fees and dues chargeable
to them are entitled to receive one copy of each volume or article
printed by the Academy, on application to the Librarian personally
or by written order, within two years from the date of publication.
And the current issues of the Proceedings shall be supplied, when
ready for publication, free of charge to all the Fellows and Members
of the Academy who desire to receive them.

3. The Committee of Publication shall fix from time to time the
price at which the publications of the Academy may be sold. But
members may be supplied at half this price with volumes which
they are not entitled to receive free, and which are needed to com-
plete their sets.

4. Two hundred extra copies of each paper accepted for publica-
tion in the Memoirs or Proceedings of the Academy shall be placed
at the disposal of the author, free of charge.

5. Resident Fellows may borrow and have out from the Library
six volumes at any one time, and may retain the same for three
months, and no longer.

6. Upon special application, and for adequate reasons assigned,
the Librarian may permit a larger number of volumes, not exceed-
ing twelve, to be drawn from the Libra^ for a limited period.

7. Works published in numbers, when unbound, shall not be
taken from the Hall of the Academy, except by special leave of the
Librarian.

8. Books, publications, or apparatus shall be procured from the
income of the Rumford Fund only on the certificate of the Rumford
Committee, that they, in their opinion, will best facilitate and
encourage the making of discoveries and improvements which may
merit the Rumford Premium.

9. The annual meeting and the other stated meetings shall be
holden at eight o'clock, P. M.

10. A meeting for receiving and discussing scientific com-
munications may be held on the second Wednesday of each month
not appointed for stated meetings, excepting July, August, and
September.

468 EUMFORD PREMIUM.

RUMFORD PREMIUM.

In conformity with the terms of the gift of Benjamin, Count
Rumford, granting a certain fund to the American Academy of Arts
and Sciences, and with a decree of the Supreme Judicial Court
for carrying into effect the general charitable intent and purpose
of Count Rumford, as expressed in his letter of gift, the Academy
is empowered to make from the income of said fund, as it now
exists, at any annual meeting, an award of a gold and silver medal,
being together of the intrinsic value of three hundred dollars, as a
premium to the author of any important discovery or useful im-
provement in light or in heat, which shall have been made and pub-
lished by printing, or in any way made known to the public, in
any part of the continent of America, or any of the American
islands; preference being always given to such discoveries as
shall, in the opinion of the Acadenr^, tend most to promote the
good of mankind; and to add to such medals, as a further
premium for such discovery and improvement, if the Academy
see fit so to do, a sum of money not exceeding three hundred
dollars.

INDEX.

A.

Acanthomyces, 36.

lasiophora, 37.
Acetacetic Ether, 158.
Acetic Ester as solvent, experiments

with, 289.
iEschynomene petrsea, 166.
Ageroniini, tribe, 249.
■ Amphichlora, 249.
Amphichlora feronia, 251.
Amphichlora fornax, 250.
Amyl Hydride, 69.

Iso-Hydride, 74.
Anartia, 237, 238.

jatrophse, 238.
Androsace cinerascens, 180.
Anhydrides, formation of, 93.
Argentic Brommethylpyromucate,

207.
Argentic Methylpyromucate, 197.

B.

Baric Brommethylpyromucate, 205.
Dibroindiuitrophenylate, 323.
Methylpyromucate, 195.
Tribromdinitrophenylate, 320.
Bellis purpurascens, 172.
Beloporone fragilis, 183.
Benzoic Acid, on the formation of
the anhydrides of, 93.
action of phosphorpentoxide in
an excess of benzol upon, 94.
Benzol, action of phosphorpentoxide
upon benzoic acid in an excess
of, 94.
action of phosphorpentoxide
upon orthonitrobenzoic acid
in an excess of, 95.
action of phosphorpentoxide
upon meta nitrobenzoic acid
in an excess of, 97.

Benzol, action of phosphorpentoxide
upon para nitrobenzoic acid
in an excess of, 98.
Benzoylformic-o-toluide, 146.

Phenylhydrazonehydrate, 148.
Bequest, —

Cyrus M. Warren, 329.
Biographical notices, list of, 355.
John Couch Adams, 444.
George Biddell Airy, 446.
Henry Jacob Bigelow, 328.
Edward Burgess, 357.
George Bassett Clark, 360.
George W. Cullum, 416.
William Prescott Dexter, 363.
John C. Fremont, 422.
Thomas Hill, 426.
Thomas Sterry Hunt, 367.
Joseph Leidy, 437.
Joseph Lovering, 372.
George Hinckley Lyman, 385.
Noah Porter, 442.
David Humphreys Storer, 388.
Cyrus Moors Warren, 391.
Sereno Watson, 391.
Wilhelm Eduard Weber, 449.
Bivalent Carbon, 102.
Boiling Points, Note on the Relative
Position of High Tempera-
ture, 100.
Bromine, action on pyromucamide,

217.
Bromine and Potassium Hydroxide,
action on /38-dibrompyromu-
camide, 214.
Bromine and Water, action of, 199,

207.
Bromine Water, action on pyromu-
camide, 219.
Brommethylpyromucate, Baric, 205.
Calcic, 206.
Argentic, 207.
Potassic, 207.

470

INDEX.

Brommethylpyromucic Acid, /3, 204.

<a,208.

co-oxy-/3, 211.
Bromnitroresorcine Diethylether,

316.
Butyl Hydride, 66.

Iso-Hydride, 66.

c.

Caesalpinia multiflora, 167.
Calcic Brommethylpyromucate, 206.
Calcic Methylpyvomucate, 196.
Casimiroa edulis, 166.
Cast Iron and Cast Nickel, Ther-
mal Conductivity of, 262.
Ceratomyces, 34.
mirabilis, 34.
camptosporus, 35.
Cleome Potosina, 165.
Cnicus excelsior, 179.
Coea, 244.
Coea acheronta, 244.
Coeini, tribe, 243.
Communications, —

Carl Barus, 13, 100.

Charles R. Cross and Hariy M.

Goodwin, 1.
Charles R. Cross and Margaret

E. Maltby, 222.
Charles R. Cross and George

V. Wendell. 271.
Edwin H. Hall, 262.
Henry B. Hill and Walter L.

Jennings, 186.
C. Loring Jackson and H. N.

Herman, 252.
C. Loring Jackson and W. H.

Warren, 280, 317.
W. W. Jacques, 19.
George D. Moore and Daniel F.

O' Regan, 93.
J. U. Nef, 102.
B. L. Robinson, 165.
Charles E. Saunders, 214.
Samuel H. Scudder, 236.
Henry Taber, 46, 163.
Roland Thaxter, 29.
Henry B. Ward, 260.
CM. Warren, 56, 89.
Condensation, Note on a Criticism
of the Author's Apparatus for
Fractional, 89.
Consonance, some Considerations re-
garding Helmholtz's Theory
of, 1.

Cordia alba, 182.
Corethromyces, 36.

Cryptobii, 36.
Coulterophytum, 168.

laxum, 169.
Crusea megalocarpa, 169.

D.

Deaths, —

Jose Maria Latino Coelho, 329.
Sir William Macleay, 349.
Grand Duke Constantin Nico-
layevitch, 349.

Diaethria, 240.

clymena, 241.

Dibromdinitrophenol, properties of,
322.

Dibromfurfuronitrile, /3S, proper-
ties of, 216.

Dibrommethylpyromucic Acid, w/3,
210.

Dibroinpyromucamide, /3S, the ac-
tion of bromine and Potas-
sium hydroxide on, 214.

Dictyanthus tuberosus, 180.

Diethylether of trinitrophloroglu-
cine, properties of, 287.

Dimethylether of trinitrophloroglu-
cine, properties of, 301.

Dioxymalonic Anilide, 122.

Dioxymalonic-o-toluide, 143.

E.

Electricity, what it is, 19.
Epicalinii, tribe, 239.
Erigeron heteromorphus, 173.
Ether, Acetacetic, 158.
Ethyl Methylpyromucate, 198.
Eunica, 239, 240.

monima, 240.
Eupatorium filicaule, 170.

Lemmoni, 171.

Schaffneri, 171.

Fellows, Associate, deceased, —
Fordyce Barker, 357.
George Washington Cullum,

349.
William Ferrel, 357.
Thomas Hill, 357.
Noah Porter, 349.
Lewis Morris Rutherfurd, 357.

INDEX.

471

Fellows, Associate, elected, —
George Park Fisher, 327.
Thomas Corwin Mendenhall,

327.
Fellows, Associate, list of, 455.
Fellows, Resident, deceased, —

Henry Ingersoll Bowditch,

349.
Edward Burgess, 357.
George Bassett Clark, 349.
Thomas Sterry Hunt, 349.
William Raymond Lee, 349.
Joseph Lovering, 357.
James Russell Lowell, 357.
George Hinckley Lyman, 357.
David Humphreys Storer, 357.
Cyrus Moors Warren, 357.
Sereno Watson, 349.
Fellows, Resident, elected, —
William Brewster, 330.
Louis Cabot, 327.
Edward Gardiner Gardiner,

330.
Abner Cheney Goodell, Jr.,

327.
Henry Marion Howe, 327.
Samuel Jason Mixter, 330.
Josiah Royce, 327.
Andrew Howland Russell, 349.
Henry Taber, 327.
Warren Uphara, 330.
Fellows, Resident, list of, 451.
Flaveria anomala, 178.
Foreign Honorary Members, de-
ceased,—
John Couch Adams, 357.
Sir George B. Airy, 357.
Anatole Francois Hue Marquis

de Caligny, 357.
August Wilhelm Hofmann,

357.
Sir Andrew Crombie Ramsay,

357.
Wilhelm Eduard Weber, 351.
Foreign Honorary Members, list of,

457.

G.

Geissolepis, 177.

susedsefolia, 177.
Gerardia punctata, 1 83.
Gonolobus suberiferus, 181.
Guaiacol, 191.

Gymnolomia canescens, 174.
Gynseciini, tribe, 242.

H.

Habenaria Pringlei, 1S4.
Heimatomyces, 30.

affinis, 31.

appendiculatus, 31.

Halipli, 32.

hyalinus, 31.

lichanophorus, 32.

marginatus, 34.

paradoxus, 32.

rhynchostoma, 33.

simplex, 30.

uncinatus, 33.
Heptyl Hydride, 76.

Iso-Hydride, 77.
Hexyl Hydride, 74.

Iso-Hydride, 75.
Historis, 244.

or ion, 245.
Hydride, Butyl and Butyl Iso-, 66.

Amyl, 69.

Hexyl, 74.

Heptyl, 76.

Xonyl, 80.

Octyl, 78.
Hydrocarbons, Researches on the
Volatile, 56.

in Pennsylvania Petroleum, 56.
Hydrochloride of Phenylimidofor-

mylchloride, 133.
Hydroxylamine Derivatives, on geo-
metrical isomerism of, 150.

Ipomcea ornithopoda, 183.
Isocyan-o-tolylchloride, 142.
Isocyanphenylchloride, 114.
Isocvan-p-tolylchloride, 149.
Iso-Hydride, Butyl, 66.

Amyl, 74.

Hexyl, 75

Heptvl, 77.

Octyl, 79.

K.

Kosteletzkya digitata, 166.

Laboulbeniaceae, Further Additions
to the North American Spe-
cies of, 29.

472

INDEX.

Laboulbenia Brachini, 40.

conipacta, 37.

contorta, 42.

curtipes, 40.

Galeritse, 39.

gibberosa, 43.

Gyrinidarum, 39.

inflata, 41.

luxurians, 38.

Nebi'ise, 45.

parvula, 41.

pedicellata, 44.

recta, 42.

Scbizogeuii, 43.

truncata, 45.

variabilis, 38.

vulgaris, 44.
Laurylene, 83.
Leptosyne pirmata, 176.
Litliospermum calcicola, 182.

revoluturn, 182.
Lopezia angustifolia, 168.

M.

Margarylene, 82.

Marpesia, 246.
chiron, 248.
coresia, 248.
peleus, 246.
pellenis, 247.

Matrices, on a Theorem of Sylves-
ter's relating to Non-degen-
erate, 46.
Note on the Representation of
Orthogonal, 163.

Melarapodium longipilum, 173.

Melting Points, Note on the Rela-
tive Position of High Tem-
perature, 100.

Mesoxalic - acid - phenylhydrazone,
124.

Mesoxanilide and its derivatives,
119.

Mesoxanilidehydrate, 122.

Mesoxanilide-phenylhydrazone, 121.

Mesoxanilid-imidechloride, 117.

Mesox-o-toluidehydrate, l43.

Mestra, 240, 241.
amymone, 241.

Meta Nitrobenzoic Acid, action of
Phosphorpentoxide in an ex-
cess of Benzol upon, 97.

Methylfurfuramide, 190.

Methylfurfurol, 186, 188.

Methylpyromucate, Argentic, 197.

Baric, 195.

Calcic, 196.

Ethyl, 198.

Potassic. 197.

Sodic, 197.
Methylpyromucic Acid, 186, 193.

Tetrabromide, 212.

N.

Nectonema Agile, Preliminary Com-
munication on the Host of,
260.

New Plants, Descriptions of, col-
lected in Mexico by C. G.
Pringle in 1890 and 1891,
with Notes upon a few other
Species, 165.

Nonyl Hydride, 80.

O.

Octyl Hydride, 78.
Iso-Hydride, 79.

Oldenlandia Pringlei, 169.

Orthogonal Matrices, Note on the
Representation of, 163.

Orthonitrobenzoic Acid, action of
Phosphorpentoxide in an ex-
cess of Benzol upon, 95.

Oxymethylpyromucic Acid, 210.

Para Nitrobenzoic Acid, action of
Phosphorpentoxide in an ex-
cess of Benzol upon, 98.

Perezia Michoacana, 179.

Petroleum, Researches on the Vola-
tile Hydrocarbons in Penn-
sylvania, 56.
examination of the, 59.
of the analyses and physical
properties of the different
bodies separated from, 66.

Phacelia namatostyla, 181.

Phenylhydrazone of Pyruvic Acid,
132.

Phenylhydrazonehydrate, Benzoyl-
formic-o-toluide, 148.

Phenylimidocarbonylchloride, 114.

Phenylisocyanide, 108.

INDEX.

473

Phonograph, some Experiments re-
lating to the Vowel Theory
of Helmholtz, 271.

Phosphorpentoxide, action upon
benzoic acid in an excess of
benzol, 91.
action upon orthonitrobenzoic
acid in an excess of benzol,
95.
action upon meta nitrobenzoic
acid in an excess of benzol,
97.
action upon para nitrobenzoic
acid in an excess of benzol,
98.

Pitch, on the least Number of Vibra-
tions necessary to determine,
222.

Porophyllum Pringlei, 178.

Potassic Brommethylpyrom ucate,
207.
Dibromdinitrophenylate, 323.
Methylpyromucate, 197.

Potassium Hydroxide and Bromine,
action on /38-dibrompyromu-
camide, 214.

Proceedings of Meetings, 325.

Prussic Acid, nature of, 156.

Pyromucamide, on Certain Deriva-
tives of, 211.
action of bromine on, 217.
action of bromine water on,

219.
Tetrabromide, properties of,
218.

Pyruvic Anilide, 129.

Pyruvic - anilide - phenylhydrazone,
132.

Pyruvic - anilide - phenylhydrazone-
hydrate, 131.

Pyruvic-anilidimidechloride, 126.

Pyruvic-o-toluide, 111.

R.

Rumford Premium, 168.
Rutyleue, 81.

Sabazia Michoacana, 173.
Smyrna, 212.

karwinskii, 213.
Sodic Benzylate, action in benzol,
310.

Sodic Benzylate, action on tribrom-

trinitrobenzol, 301.
Sodic Ethvlate, action in ethyl al-
cohol, 295.
action on certain derivatives of
tribromtrinitrobenzol contain-
ing alkyloxy radicals, 313.
action on the triphenylether of

trinitrophloroglucine, 313.
action on tribromnitroresorcine

diethylether, 315.
action with benzol and alcohol,

296.
quantitative study of its ef-
fect on tribromtrinitrobenzol,
292.
Sodic Isoamylate, action in benzol,

310.
Sodic Isopropylate, action in benzol,
310.
action on tribromtrinitroben-
zol, 303.
Sodic Methylate, action in benzol,
309.
action on tribromtrinitroben-
zol, 300.
Sodic Methylpyromucate, 197.
Sodic Phenylate, action in benzol,

311.
Sodic Propylate, action en tribrom-
trinitrobenzol, 302.
Sodic Propylate (Normal), action in

benzol, 309.
Spilanthes Beccatunga, 176.

disciformis, 176.
Standing Votes, 167.
Statutes, 159.

Sulphuric Acid, concentrated, action
of, 202.

T.

Tigridia pulchella, 181.
Tithonia brachypappa, 171.
Tolylimidocarbonylchloride, 112,

119.
Tolylisocyanide, 138.
Tradescantia angustifolia, 185.
Trianilidodinitrobenzol, and certain
Related Compounds, 252.
and Chloroform, 256.
experiments with, 253.
Tribromdinitrobenzol, Action of
Water upon, 317.
action upon water and sodic
carbonate, 322.

474

INDEX.

Tribromdinitrophenol, properties of,

320.
Tribrornnitroresorcine Diethylether,

preparation of, 291.
Tribromtrinitrobenzol, Action of
Water upon, 317.
action of sodic ethylate on, 283.
action of water and sodic car-
bonate upon, 318.
reactions of sodic alcobolates

with, 280.
quantitative study of the action
of sodic ethylate on, 292.
Triisopropylether of Trinitrophloro-
glucine, properties of the, 304.
TrinitrophloroglucineTriethylether,
properties of, 285.
preparation of, 291.
Tribenzylether, properties of,
305.
Triorthotoluidodinitrobenzol, 258.

properties of, 259.
Triparatoluidinitrobenzol, 257.
Triparatoluidodinitrobenzol, proper-
ties of, 258.
Tripropylether of Trinitrophloro-
glucine, properties of the nor-
mal, 303.

Tropical Faunal Element of our
Southern Nymphalinse sys-
tematically treated, 236.

Tymetes Boisduval, 248.

Tymetini, tribe, 245.

V.

Valeriana albonervata, 170.
Verbesina Potosina, 175.

Pringlei, 175.
Victorina, 237.

Stelenes, 237.
Victoriniini, tribe, 236.
Vigna luteola, 167.
Vigna strobilophora, 167.
Viola reptans, 165.
Viscosity, Dependence of, on Pres-
sure and Temperature, 13.

X.

Xanthocephalum tomentellum, 172.
Xylosma Pringlei, 166.

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